aco: implement nir_intrinsic_load_global on GFX6

GFX6 doesn't have FLAT instructions, use MUBUF instructions instead.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/merge_requests/3477>
1 file changed