msm: gpio: Add v2 gpio support to MSM SoCs.

Beginning with the MSM8x60, the hardware block responsible for gpio
support changes.  Provide gpiolib support for the new v2 architecture.

Cc: Baruch Siach <baruch@tkos.co.il>
Cc: Pavan Kondeti <pkondeti@codeaurora.org>
Signed-off-by: Gregory Bean <gbean@codeaurora.org>
Signed-off-by: Daniel Walker <dwalker@codeaurora.org>