drm/rockchip: vop: Fix call to crtc reset helper

drm/rockchip: vop: Fix call to crtc reset helper

[ Upstream commit 5aacd290837828c089a83ac9795c74c4c9e2c923 ]

Allocation of crtc_state may fail in vop_crtc_reset, causing an invalid
pointer to be passed to __drm_atomic_helper_crtc_reset.

Fix this by adding a NULL check of crtc_state, similar to other drivers.

Fixes: 01e2eaf40c9d ("drm/rockchip: Convert to using __drm_atomic_helper_crtc_reset() for reset.")
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230621223311.2239547-4-jonas@kwiboo.se
Signed-off-by: Sasha Levin <sashal@kernel.org>