dt-bindings: pinctrl: qcom: Add sc7280 lpass lpi pinctrl bindings

Add device tree binding Documentation details for Qualcomm SC7280
LPASS LPI pinctrl driver.

Signed-off-by: Srinivasa Rao Mandadapu <quic_srivasam@quicinc.com>
Co-developed-by: Venkata Prasad Potturu <quic_potturu@quicinc.com>
Signed-off-by: Venkata Prasad Potturu <quic_potturu@quicinc.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/1650285427-19752-3-git-send-email-quic_srivasam@quicinc.com


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