Add SDA and SCL pin numbers to i2c platform data

Patch adds SDA and SCL pin numbers to the i2c platform data
structure for Davinci DM355 and DM6446. This at present is
used for i2c bus recovery.
TODO: Add SDA and SCL pin number information to include all
Davinci platforms such as dm355-leopard, dm365, dm646x, da8xx etc.

Signed-off-by: Philby John <pjohn@in.mvista.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>