radv: remove call to nir_lower_pack()

The pack_* instructions are now lowered via nir_lower_alu_to_scalar()
and unpack_* are not lowered anymore.

These bitcasts are no-ops, and lowering prevents
some optimizations like vectorization.

Note: There are still some *_split variations remaining
from different other NIR passes.

Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6527>
1 file changed