This change is needed to properly lock I2C bus driver, which serves DDC.

Prior to this change i2c_put_adapter() is misused, which may lead to
an overflow over zero of I2C bus driver user counter.
Signed-off-by: NVladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: NTomi Valkeinen <tomi.valkeinen@ti.com>