dt-bindings: pinctrl: qcom: adjust description

Drop "binding" from description, because the field should describe the
hardware.

Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20221017230012.47878-34-krzysztof.kozlowski@linaro.org


Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>