drm/panthor: Interrupt group start/resumption if group_bind_locked() fails

drm/panthor: Interrupt group start/resumption if group_bind_locked() fails

group_bind_locked() can fail if the MMU block is stuck. This is normally
a reset situation, but by the time we reset the GPU, we might have
tried to resume a group that's not resident, which will probably trip
out the FW. So let's avoid that by bailing out when group_bind_locked()
returns an error. We don't even try to start more groups because the
GPU will be reset anyway.

Fixes: de8548813824 ("drm/panthor: Add the scheduler logical block")
Reported-by: sashiko-bot@kernel.org
Closes: https://sashiko.dev/#/patchset/20260623-panthor-signal-from-irq-v3-0-2ece396f8ee0@collabora.com?part=7
Signed-off-by: Boris Brezillon <boris.brezillon@collabora.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>
Link: https://patch.msgid.link/20260625-panthor-misc-fixes-v1-10-b67ed973fea6@collabora.com