ARM: dts: rk3588-rock-5b-u-boot: add bootph-all to pinctrl for sdmmc

To be able to initialize the pinctrl correctly at SPL level and read
u-boot proper from SD-Card, the pinctrl must be initialized.

Signed-off-by: Eugen Hristev <eugen.hristev@collabora.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>