ARM: dts: vf610-zii-dev-rev-b: Remove I2C3

I2C3 bus was only brought out in revision A1 of the board and revision
B1 only brings out 3 I2C busses (I2C0, I2C1 and I2C2).

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>