drm/panel: nt36523: fix return value check in nt36523_probe()

stable inclusion
from stable-v6.6.5
commit 684cf5d6aef1a8d5355cc23d3f0577513575833a
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I8N21P

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=684cf5d6aef1a8d5355cc23d3f0577513575833a



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[ Upstream commit fb18fe0fdf22a2f4512a8b644bb5ea1473829cda ]

mipi_dsi_device_register_full() never returns NULL pointer, it
will return ERR_PTR() when it fails, so replace the check with
IS_ERR().

Fixes: 0993234a ("drm/panel: Add driver for Novatek NT36523")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://lore.kernel.org/r/20231129090715.856263-1-yangyingliang@huaweicloud.com


Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20231129090715.856263-1-yangyingliang@huaweicloud.com


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