ARM: dts: vf610: Extend I2C support to all available buses.

This commit extends the existing Vybrid I2C support to cover buses i2c1,
i2c2, and i2c3.  Based in (very) large part on an initial patch by
Stefan Agner that was just lacking a couple of DMA assignments.

Signed-off-by: Cory Tusar <cory.tusar@pid1solutions.com>
Acked-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Shawn Guo <shawn.guo@linaro.org>