The logic at V4L2 led core assumes that the flash struct
can be null. However, it doesn't check for null while
trying to set, causing some smatch  to warn:

	drivers/media/v4l2-core/v4l2-flash-led-class.c:210 v4l2_flash_s_ctrl() error: we previously assumed 'fled_cdev' could be null (see line 200)
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>
Acked-by: NSakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: NMauro Carvalho Chehab <mchehab@s-opensource.com>