OMAP: I2C: Convert i2c driver to use PM runtime api's

This patch converts the i2c driver to use PM runtime apis

Signed-off-by: Rajendra Nayak <rnayak@ti.com>
Cc: Paul Walmsley <paul@pwsan.com>
Cc: Jean Delvare <khali@linux-fr.org>
Acked-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>