[media] dt3155v4l: vb2_queue_init() can now fail. Check is required

drivers/staging/media/dt3155v4l/dt3155v4l.c: In function 'dt3155_open':
drivers/staging/media/dt3155v4l/dt3155v4l.c:399:17: warning: ignoring return value of 'vb2_queue_init', declared with attribute warn_unused_result [-Wunused-result]

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>