arm64: dts: qcom: sm6125-seine: Configure SD Card slot on SDHCI 2

Sony's seine board features an SD Card slot on SDHCI 2, that is to be
powered by l5 and l22.  The card detect pin is already biased via
updates on the generic sdc2_*_state pinctrl nodes.

As usual regulator voltages are decreased to the maximum voted by the
downstream driver for safety.  SDHCI 2 is the only hardware block
feeding off of these.

Signed-off-by: Marijn Suijten <marijn.suijten@somainline.org>
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
Link: https://lore.kernel.org/r/20221222203636.250190-5-marijn.suijten@somainline.org