Input: synaptics_i2c - convert to dev_pm_ops

There is a general move to convert drivers to dev_pm_ops rather than bus
specific PM ops in order to facilitate core development. Do this converison
for synaptics-i2c.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>