radeonsi: fix up buffer descriptor upper-bound checking
radeonsi: fix up buffer descriptor upper-bound checking

st/mesa does this too, so we're safe.

Reviewed-by: Nicolai Hähnle <0d0be6cf5ad662651be2dc5dfd44aa2b09d4c1cc@amd.com>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler