drm/amdkfd: Add gfx12 trap handler support

- HWREG changes since gfx11
- Save/restore barrier state
- get_wave_size is now reserved by assembler

v2: rebase (Alex)
Signed-off-by: Jay Cornwall <jay.cornwall@amd.com>
Reviewed-by: Harish Kasiviswanathan <Harish.Kasiviswanathan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>