input: atmel_mxt_ts: add support for pinctrl framework

Add support for pinctrl framework for GPIO configuration so
that the Atmel touch controller driver is compatible with
targets that use and targets that don't use pinctrl framework.
Also configured the gpio and pinctrl in driver suspend/resume
method for the run time power consumption.

Change-Id: Icacc96367081953ae08f4fbee954f15c216f1d98
Signed-off-by: Sarada Prasanna Garnayak <c_sgarna@codeaurora.org>