drm/amdkfd: disable shader message vgpr deallocation on gc 12.1

drm/amdkfd: disable shader message vgpr deallocation on gc 12.1

Shader messages to deallocate VGPRs prior to shader end can prevent
the trap handler from saving context, making debugging and core dumps
unreliable.

VGPR deallocations for performance gain is negligible.
GC 12.1 will NOP shader VGPR deallocation messages via HW
settings on driver boot.

Signed-off-by: Jonathan Kim <jonathan.kim@amd.com>
Acked-by: Harish Kasiviswanathan <harish.kasiviswanathan@amd.com>
Reviewed-by: Felix Kuehling <felix.kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>