Add the mesa-clc dependency, put its staged usr/bin on PATH so meson's
find_program(native) resolves mesa_clc/vtn_bindgen2, and pass -Dmesa-clc=system
-Dprecomp-compiler=system. This resolves the cross-build structural error where
vtn_bindgen2 (native) linked target libs; with_clc now flips false so the cross
build no longer builds the in-tree CLC infra. Verified: cross mesa finds both
tools YES and passes every dependency + CLC gate (next blocker is the Redox
gallium winsys port).
vasilito
e35feb1dbe