ARM: shmobile: alt: add VIN0, ADV7180 DT support

Adds the device board-dependent part of the VIN0 device and its ADV7180
video decoder on I2C1, and the interconnection between them.

Based on silk patch by Sergei Shtylyov.

Signed-off-by: Ulrich Hecht <ulrich.hecht+renesas@gmail.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>