drm/virtio: Fix double free on probe failure

stable inclusion
from stable-5.10.51
commit d2d17ca924f4360c262fab9f4515d04d2a3c4e08
bugzilla: 175263 https://gitee.com/openeuler/kernel/issues/I4DT6F

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=d2d17ca924f4360c262fab9f4515d04d2a3c4e08



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[ Upstream commit cec7f177 ]

The virtio_gpu_init() will free vgdev and vgdev->vbufs on failure.
But such failure will be caught by virtio_gpu_probe() and then
virtio_gpu_release() will be called to do some cleanup which
will free vgdev and vgdev->vbufs again. So let's set dev->dev_private
to NULL to avoid double free.

Signed-off-by: Xie Yongji <xieyongji@bytedance.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20210517084913.403-2-xieyongji@bytedance.com


Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Acked-by: Weilong Chen <chenweilong@huawei.com>
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>