[BUILD] cmake fails to configure vdb_tool when -DOPENVDB_TOOL_USE_EXR=ON

### Environment
**Operating System:** Gentoo 2.9
**Version / Commit SHA:** VDB 10.0.1
**CMake Version:** 3.25.1
**Compiler:** gcc 11

### Describe the problem
Trying to build the vdb_tool binary fails in cmake configuration, because it uses OpenEXR-2 library OpenEXR:IlmImf. Replacing the link line and using OpenEXR:OpenEXR as the link library for OpenEXR-3 let the tool be built. The error is:
```
-- Configuring done
CMake Error at openvdb_cmd/vdb_tool/CMakeLists.txt:96 (target_link_libraries):
The link interface of target "vdb_tool_common" contains:

OpenEXR::IlmImf

but the target was not found. Possible reasons include:

* There is a typo in the target name.
* A find_package call is missing for an IMPORTED target.
* An ALIAS target is missing.

-- Generating done
```

### To Reproduce
Steps to reproduce the behavior:
1. Download the 10.0.1 release tarball from GitHub
2. Run CMake
```
cmake -G Ninja -DCMAKE_INSTALL_PREFIX=/usr -DCMAKE_INSTALL_DOCDIR=share/doc/openvdb-10.0.1/ -DOPENVDB_ABI_VERSION_NUMBER=10 -DOPENVDB_BUILD_DOCS=no -DOPENVDB_BUILD_UNITTESTS=yes -DOPENVDB_BUILD_VDB_LOD=yes -DOPENVDB_BUILD_VDB_RENDER=yes -DOPENVDB_BUILD_VDB_TOOL=yes -DOPENVDB_BUILD_VDB_VIEW=yes -DOPENVDB_CORE_SHARED=ON -DOPENVDB_CORE_STATIC=no -DOPENVDB_ENABLE_RPATH=OFF -DUSE_AX=no -DUSE_BLOSC=no -DUSE_CCACHE=OFF -DUSE_COLORED_OUTPUT=ON -DUSE_EXR=yes -DUSE_IMATH_HALF=ON -DUSE_LOG4CPLUS=ON -DUSE_NANOVDB=no -DUSE_PKGCONFIG=ON -DUSE_PNG=yes -DUSE_STATIC_DEPENDENCIES=no -DUSE_TBB=ON -DUSE_ZLIB=no -DBUILD_TEST=yes -DOPENVDB_BUILD_VDB_AX=no -DOPENVDB_TOOL_NANO_USE_BLOSC=OFF -DOPENVDB_TOOL_USE_ABC=OFF -DOPENVDB_TOOL_USE_EXR=ON -DOPENVDB_TOOL_USE_JPG=ON -DOPENVDB_TOOL_USE_NANO=no -DOPENVDB_TOOL_USE_PNG=ON -DOPENVDB_SIMD=AVX -DCMAKE_BUILD_TYPE=RelWithDebInfo
```
3. See error above

### Additional context
I removed the command line options for our toolchain file and initial cache from the above command for better readability. They don't have an influence on the outcome.