gpio: msm: Add device tree and irqdomain support for gpio-msm-v2

This cleans up the gpio-msm-v2 driver of all the global define usage.
The number of gpios are now defined in the device tree. This enables
adding irqdomain support as well.

Signed-off-by: Rohit Vaswani <rvaswani@codeaurora.org>
Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: David Brown <davidb@codeaurora.org>