drm/fsl-dcu: Remove redundant dev_err()

There is no need to call the dev_err() function directly to print a
custom message when handling an error from platform_get_irq() function
as it is going to display an appropriate error message in case of a
failure.

Signed-off-by: Chen Ni <nichen@iscas.ac.cn>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Acked-by: Alison Wang <alison.wang@nxp.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240918074841.2221210-1-nichen@iscas.ac.cn


Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>