drm/radeon: fix race condition UAF in radeon_gem_set_domain_ioctl

stable inclusion
from stable-v5.10.186
commit d8efc77f23c84a46bd8a43bec833cf637222b2bf
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I8J4KH

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d8efc77f23c84a46bd8a43bec833cf637222b2bf



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[ Upstream commit 982b173a ]

Userspace can race to free the gobj(robj converted from), robj should not
be accessed again after drm_gem_object_put, otherwith it will result in
use-after-free.

Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Min Li <lm0963hack@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>