pinctrl: Add wakeup gpio register and bit information

Add wake_reg and wake_bit fields into msm_pingroup structure.
This will be used to configure gpios as wakeup capable.

Change-Id: I19237d16132f014496e9a8a1c718d492e290d5fe
Signed-off-by: Rishabh Bhatnagar <rishabhb@codeaurora.org>