media: i2c: adv7180: Use MEDIA_BUS_FMT_UYVY8_1X16 for CSI2 output

CSI2 devices are meant to use the 1Xnn formats rather than 2Xnn
such as MEDIA_BUS_FMT_UYVY8_2X8.

For devices with ADV7180_FLAG_MIPI_CSI2 set, use
MEDIA_BUS_FMT_UYVY8_1X16.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>