graphics/mesa-devel: hook BINARY_ALIAS into --native-file

Meson probes FreeBSD suffixes[1] for llvm-config but ends up selecting
the last match instead of the unsuffixed version. Given BINARY_ALIAS
is not respected this breaks dependency tracking. So, help Meson find
the correct tool by translating into its own aliasing facility.

[1] https://github.com/mesonbuild/meson/blob/0.54.2/mesonbuild/environment.py#L185-L198