input: touchscreen: Change touch driver suspend code flow for XO shutdown

ITE tech touch driver puts the controller to IDLE state in suspend
function through an i2c write into controller register space. But
due to multiple triggers of fb blank events, the suspend
function is called repeatatively without resume, and the driver
causes i2c nacks in suspend function while again putting the
controller is IDLE state. This keeps the QUP5 clock ON and XO shutdown
doesn't happen.
This change prevents the touch driver to execute the i2c write, to
put the controller in IDLE state, by repeatative fb blank events,
and causes XO shutdown to happen within time limits.

Change-Id: Ie3ee6b861c10ae901dea54f252f6a799d688f02a
Signed-off-by: Shantanu Jain <shjain@codeaurora.org>