media: mx2_emmaprp: Check for platform_get_irq() error

platform_get_irq() may fail, so we should better check its return
value and propagate it in the case of error.

Signed-off-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>