meson: fix some build warnings
What does this MR do and why?
Hi, here are two small build fixes for the following meson warnings:
src/nouveau/compiler/meson.build:52: WARNING: Project targets '>= 1.1.0' but uses feature introduced in '1.3.0': rust_abi arg in static_library.
and
DEPRECATION: "pkgconfig" entry is deprecated and should be replaced by "pkg-config"
More details are in the commit messages.
These remove some distractions in the build logs.
I am not sure if requiring meson 1.3.0 for the whole project is viable or desirable, but it is a fact that some build files are using features that require it.
Thanks, Antonio