Part revert "gallium/auxiliary: don't build NIR sources with MSVC2008 flags"
Part revert "gallium/auxiliary: don't build NIR sources with MSVC2008 flags"

This reverts commit 41c7912d04111a7e3b75a438c5cbbd7edc0fee25 but leaves
out the pragma [that inspired the original commit].

Building mesa requires MSVC2013 or later, thus we no longer need this.

v2: Use correct include path (src/glsl/nir -> src/compiler/nir)

Conflicts:
	src/gallium/auxiliary/Makefile.am

Acked-by: Jason Ekstrand <68c46a606457643eab92053c1c05574abb26f861@jlekstrand.net> (v1)

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler