drm/amdkfd: Apply VGPR bank state fixup on gfx12.1 trap exit

drm/amdkfd: Apply VGPR bank state fixup on gfx12.1 trap exit

- Identify co-issue of S_SET_VGPR_MSB and VALU with banked VGPR
- Restore previous bank setting when exiting the trap

v2:
- Refine VOP3PX2 detection
- Improve load pipelining
- Fix a comment typo

Signed-off-by: Jay Cornwall <jay.cornwall@amd.com>
Reviewed-by: Lancelot Six <lancelot.six@amd.com>
Cc: Joseph Greathouse <joseph.greathouse@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>