Initialization of TRAP_DATA0/1 is still required for the debugger to detect
new waves on Aldebaran.  Also, per-vmid global trap enablement may be
required outside of debugger scope so move to init phase.

v2: just add the gfx 9.4.2 changes (Alex)
Signed-off-by: Jonathan Kim <Jonathan.Kim@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>