pinctrl: qcom: spmi-mpp: Add PM8937 compatible

[ Upstream commit f7552611 ]

The PM8937 provides 4 MPPs.
Add a compatible to support them.

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Barnabás Czémán <barnabas.czeman@mainlining.org>
Link: https://lore.kernel.org/20241031-msm8917-v2-4-8a075faa89b1@mainlining.org


Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>