media: ipu3-cio2: Fix mbus_code processing in cio2_subdev_set_fmt()

Loop was useless as it would always exit on the first iteration. Fix
it with right condition.

Signed-off-by: Pavel Machek (CIP) <pavel@denx.de>
Fixes: a86cf9b2 ("media: ipu3-cio2: Validate mbus format in setting subdev format")
Tested-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: stable@vger.kernel.org # v4.16 and up
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>