usb: type_c: pericom: Allow disabling chip on system suspend

If pericom chip is enabled using GPIO on bootup then keeping it
always enabled may increase rock bottom current of system by few
micro-amps. Provide an option to use to allow disabling the chip
during suspend if state is not-attached using DT or module param.
Command to enable this at runtime:
  echo 1 >  /sys/module/type_c_pericom/parameters/disable_on_suspend

Only side-effect of enabling suspend during LPM is that ID High->Low
transition (or host cable connection) won't be detected when device
is in suspend state. Cable detection will happen when system wakes-up.

Change-Id: I0526bc7b1e752e8490189fbb1ed17973e9c492fd
Signed-off-by: Manu Gautam <mgautam@codeaurora.org>