omap4: Add i2c board support on omap4430 sdp platform

This patch adds the i2c board support for OMAP4430 SDP platform.

Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Balaji T K <balajitk@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>