dt-bindings: pinctrl: qcom-pmic-gpio: Add pmx55 support

Add support for the PMX55 GPIO support to the Qualcomm PMIC GPIO
binding.

Signed-off-by: Vinod Koul <vkoul@kernel.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Link: https://lore.kernel.org/r/20201126092151.1082697-1-vkoul@kernel.org


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>