media: verisilicon: Do not check for 0 return after calling platform_get_irq()

It is not possible for platform_get_irq() or platform_get_irq_byname()
to return 0. Use the return value from platform_get_irq()
or platform_get_irq_byname().

Signed-off-by: Ruan Jinjie <ruanjinjie@huawei.com>
Reviewed-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>