drm/rockchip: vop: Don't crash for invalid duplicate_state()

stable inclusion
from stable-v5.10.137
commit 9f416e32eda913bf31d6ae2915584e0d994bece1
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I60PLB

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=9f416e32eda913bf31d6ae2915584e0d994bece1



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[ Upstream commit 1449110b ]

It's possible for users to try to duplicate the CRTC state even when the
state doesn't exist. drm_atomic_helper_crtc_duplicate_state() (and other
users of __drm_atomic_helper_crtc_duplicate_state()) already guard this
with a WARN_ON() instead of crashing, so let's do that here too.

Fixes: 4e257d9e ("drm/rockchip: get rid of rockchip_drm_crtc_mode_config")
Signed-off-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220617172623.1.I62db228170b1559ada60b8d3e1637e1688424926@changeid


Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Reviewed-by: Wei Li <liwei391@huawei.com>