drm/amdgpu: set COMPUTE_PGM_RSRC1 for SGPR/VGPR clearing shaders

Otherwise, the SQ may skip some of the register writes, or shader waves may
be allocated where we don't expect them, so that as a result we don't actually
reset all of the register SRAMs. This can lead to spurious ECC errors later on
if a shader uses an uninitialized register.

Signed-off-by: Nicolai Hähnle <nicolai.haehnle@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org