vgsp-disp: fix disp.lock self-deadlock; backfill h_object from the alloc

gsp_disp_engine_channel_add() took disp.lock and then called the
self-locking gsp_disp_find_object(), deadlocking the RPC thread on the
first display push-buffer control (r1621c: watchdog hard lockups in
gsp_emu_0 channel_add+0x13b and gsp-sema-svc pump+0x88, R13=0xc57d).
Use a caller-holds-lock helper instead.

The push-buffer control arrives before the alloc (control, registration,
alloc), so a channel registered from the control had h_object=0 and the
completion-event post stayed inert.  Backfill h_object when the alloc
note lands for a registered channel.

0 files changed, 0 insertions, 0 deletions