drm/amd/amdgpu: Put in rest of wave fields

Add the rest of the basic SQ WAVE fields to
finish off the implementation.  Eventually,
a separate interface will be needed for GPRs.

Signed-off-by: Tom St Denis <tom.stdenis@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>