spi: spi-qcom-qspi: Support pinctrl sleep states

It's fairly common practice for drivers to switch to a "sleep" pinctrl
state at the end of its runtime_suspend function and then back to
"default" at the beginning of runtime_resume. Let's do that for
spi-qcom-qspi.

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20230323102605.5.I79544b9486033bd7b27f2be55adda6d36f62a366@changeid
Signed-off-by: Mark Brown <broonie@kernel.org>