Revert "radv,aco: allow unaligned LDS access on GFX9+"

Revert "radv,aco: allow unaligned LDS access on GFX9+"

This reverts commit 1a0b0e8460c1881f94975b3dfbe9c312d9c3fcf7.

The bounds checking behaviour of ds_read_b64, ds_read_b96 and ds_read_b128
make this feature very difficult to use safely.

This fixes a blocking artifact in Hitman 2. Previously, it contained:
ds_read_b64(local_invocation_index() * 4 - 4)
For local_invocation_index()=0, the second dword would be considered
out-of-bounds, even though it's at offset 0.

Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9332>