ARM: dts: qcom: Replace gpio node with pinctrl node

Replace the standalone gpio driver with pinctrl-msm as we now have
msm8660 support there.

Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Andy Gross <agross@codeaurora.org>