I2C: OMAP: Fix the mismatch of pm_runtime enable and disable

Currently the i2c driver calls the pm_runtime_enable and never
the disable. This may cause a warning when pm_runtime_enable
checks for the count match.Fix the same by calling
pm_runtime_disable in the error and the remove path.

Cc: Rajendra Nayak <rnayak@ti.com>
Acked-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Shubhrajyoti D <shubhrajyoti@ti.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>