protobuf 25.2 broken for cross compiles

A simple
```meson
project('my_project', 'cpp')

protoc = subproject('protobuf').get_variable('protoc')
```

while cross compiling, gives the error:
```
subprojects/protobuf-25.2/src/meson.build:29:18: ERROR: Tried to tied to mix a host machine library ("absl_base") with a build machine target "protoc-native" This is not possible in a cross build.
```

Full repository: [julianneswinoga/meson_protobuf_bug](https://github.com/julianneswinoga/meson_protobuf_bug)
Full logs: [meson-log.txt](https://github.com/user-attachments/files/18349698/meson-log.txt)

Reproduce the failure with the linked julianneswinoga/meson_protobuf_bug repository and inspect subprojects/protobuf-25.2/src/meson.build around line 29, alongside meson-log.txt. Trace how protoc-native and the host-machine absl_base library are selected during cross compilation; done means the minimal project can obtain protoc without the reported machine-mixing error.

Written by the indexing model from the issue text.