drm/msm: Fix VM_BIND UNMAP locking

drm/msm: Fix VM_BIND UNMAP locking

Wrong argument meant that the objs involved in UNMAP ops were not always
getting locked.

Since _NO_SHARE objs share a common resv with the VM (which is always
locked) this would only show up with non-_NO_SHARE BOs.

Reported-by: Victoria Brekenfeld <victoria@system76.com>
Fixes: 2e6a8a1fe2b2 ("drm/msm: Add VM_BIND ioctl")
Closes: https://gitlab.freedesktop.org/drm/msm/-/issues/94
Signed-off-by: Rob Clark <robin.clark@oss.qualcomm.com>
Patchwork: https://patchwork.freedesktop.org/patch/713898/
Message-ID: <20260324220519.1221471-2-robin.clark@oss.qualcomm.com>