Cannot compile for embedded aarch64 without GLFW (and other stuff?) even with BUILD_GUI=OFF

Hello, I am trying to build Open3D for an arm64 embedded sytem. I just want to build the core library, I don't need visualization, or CUDA, or anything fancy, just the core geometry module for point clouds and meshes, that's it. It seems that even though I explicitly disabled the GUI, it is still trying to build GLFW and other libraries which are related to window management and visualization. Is there a way to disable them?

### Checklist

- [X] I have searched for [similar issues](https://github.com/isl-org/Open3D/issues).
- [X] For Python issues, I have tested with the [latest development wheel](https://www.open3d.org/docs/latest/getting_started.html#development-version-pip).
- [X] I have checked the [release documentation](https://www.open3d.org/docs/release/) and the [latest documentation](https://www.open3d.org/docs/latest/) (for `main` branch).

### Steps to reproduce the issue

#### I first cloned Open3D v0.18.0 by:
```
git clone https://github.com/isl-org/Open3D.git -b v0.18.0
cd Open3D
```

#### Then, I build Open3D in the build environment for the embedded platform I'm using (`cmake` is a cmake wrapper passing the correct toolchain to cmake):
```
cmake -DCMAKE_BUILD_TYPE=Release -DBUILD_EXAMPLES=OFF -DBUILD_PYTHON_MODULE=OFF -DBUILD_ISPC_MODULE=OFF -DBUILD_GUI=OFF -DUSE_SYSTEM_CURL=ON -DUSE_SYSTEM_EIGEN3=ON -DUSE_SYSTEM_TBB=ON ..
```

### Error message

```shell
cmake -DCMAKE_BUILD_TYPE=Release -DBUILD_EXAMPLES=OFF -DBUILD_PYTHON_MODULE=OFF -DBUILD_ISPC_MODULE=OFF -DBUILD_GUI=OFF -DUSE_SYSTEM_CURL=ON -DUSE_SYSTEM_EIGEN3=ON -DUSE_SYSTEM_TBB=ON ..
-- CMAKE_BUILD_TYPE is set to Release.
-- ccache found at /bsp/host/bin/ccache
-- Downloading third-party dependencies to /home/giuliano/Open3D/3rdparty_downloads
CMake Deprecation Warning at CMakeLists.txt:196 (cmake_policy):
The OLD behavior for policy CMP0072 will be removed from a future version
of CMake.

The cmake-policies(7) manual explains that the OLD behaviors of all
policies are deprecated and that a policy should be set to OLD only under
specific short-term circumstances. Projects should be ported to the NEW
behavior and not rely on setting a policy to OLD.

-- The C compiler identification is GNU 7.3.1
-- The CXX compiler identification is GNU 7.3.1
-- Detecting C compiler ABI info
-- Detecting C compiler ABI info - done
-- Check for working C compiler: /bsp/host/bin/aarch64-linux-gnu-gcc - skipped
-- Detecting C compile features
-- Detecting C compile features - done
-- Detecting CXX compiler ABI info
-- Detecting CXX compiler ABI info - done
-- Check for working CXX compiler: /bsp/host/bin/aarch64-linux-gnu-g++ - skipped
-- Detecting CXX compile features
-- Detecting CXX compile features - done
-- Open3D 0.18.0+5c982c7b5
-- Found Python3: /bsp/host/bin/python3.11 (found suitable version "3.11.6", minimum required is "3.6") found components: Interpreter Development Development.Module Development.Embed
-- Performing Test FLAG_fstack_protector_strong
-- Performing Test FLAG_fstack_protector_strong - Success
-- Performing Test FLAG_Wformat
-- Performing Test FLAG_Wformat - Success
-- Performing Test FLAG_Wformat_security
-- Performing Test FLAG_Wformat_security - Success
-- Performing Test FLAG_Wl__z_noexecstack
-- Performing Test FLAG_Wl__z_noexecstack - Success
-- Performing Test FLAG_Wl__z_relro__z_now
-- Performing Test FLAG_Wl__z_relro__z_now - Success
-- Performing Test FLAG_pie
-- Performing Test FLAG_pie - Success
-- Performing Test FLAG____CONFIG_Release__LINKER___strip_debug_
-- Performing Test FLAG____CONFIG_Release__LINKER___strip_debug_ - Success
-- Using security hardening compiler flags: $<$:-Xcompiler=-fstack-protector-strong,-Wformat,-Wformat-security>;$<$:-fstack-protector-strong;-Wformat;-Wformat-security>
-- Using security hardening linker flags: $<$:-Xcompiler=-Wl,-z,noexecstack,-Wl,-z,relro,-z,now,$<$,EXECUTABLE>:-pie>,$<$:LINKER:--strip-debug>>;$<$:-Wl,-z,noexecstack;-Wl,-z,relro,-z,now;$<$,EXECUTABLE>:-pie>;$<$:LINKER:--strip-debug>>
-- Using security hardening compiler definitions: _FORTIFY_SOURCE=2
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD
-- Performing Test CMAKE_HAVE_LIBC_PTHREAD - Failed
-- Check if compiler accepts -pthread
-- Check if compiler accepts -pthread - yes
-- Found Threads: TRUE
-- Using installed third-party library 3rdparty_threads
-- Found OpenMP_C: -fopenmp (found version "4.5")
-- Found OpenMP_CXX: -fopenmp (found version "4.5")
-- Found OpenMP: TRUE (found version "4.5")
-- Using installed third-party library 3rdparty_openmp
-- Building with OpenMP
-- Using installed third-party library 3rdparty_x11
-- Using installed third-party library 3rdparty_eigen3 3.4.0
-- Building library 3rdparty_glfw from source
-- Could NOT find Vulkan (missing: VULKAN_INCLUDE_DIR)
-- Using X11 for window creation
-- Found X11: /bsp/host/aarch64-buildroot-linux-gnu/sysroot/usr/include
CMake Error at 3rdparty/glfw/CMakeLists.txt:236 (message):
The RandR headers were not found
```

### Open3D, Python and System information

```markdown
- Operating system: Customized Embedded Linux
- Open3D version: 0.18.0
- System architecture: arm64
- How did you install Open3D?: build from source
- Compiler version (if built from source): gcc-7
```

### Additional information

I just want to build the core library, I don't need visualization, or CUDA, or anything fancy, just the core geometry module for point clouds and meshes, that's it.