imx7d-sdb: Sync devicetree with kernel 6.5-rc1

Commit 0aea5dda ("ARM: dts: imx7d-sdb-u-boot: Fix usdhc1 UHS
operation") did a temporary workaround by addng the usdhc1 fix
inside the -u-boot.dtsi file.

The imx7d-sdb.dts from kernel 6.5-rc1 contains the proper UHS
fix, so sync the devicetree tree and remove the previous fix
from -u-boot.dtsi.

Also, adjust the PMIC node name inside pmic_get() to match
the devicetree update.

Signed-off-by: Fabio Estevam <festevam@denx.de>