drm/msm/hdmi: Add missing check for alloc_ordered_workqueue

drm/msm/hdmi: Add missing check for alloc_ordered_workqueue

[ Upstream commit afe4cb96153a0d8003e4e4ebd91b5c543e10df84 ]

Add check for the return value of alloc_ordered_workqueue as it may return
NULL pointer and cause NULL pointer dereference in `hdmi_hdcp.c` and
`hdmi_hpd.c`.

Fixes: f6e537271c7c ("drm/msm/hdmi: add hdmi hdcp support (V3)")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/517211/
Link: https://lore.kernel.org/r/20230106023011.3985-1-jiasheng@iscas.ac.cn
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>