rockchip: rk3308: Fix loading FIT from SD-card when booting from eMMC

rockchip: rk3308: Fix loading FIT from SD-card when booting from eMMC

When RK3308 boards run SPL from eMMC and fail to load FIT from eMMC due
to it being missing or checksum validation fails there can be a fallback
to read FIT from SD-card. However, without proper pinctrl configuration
reading FIT from SD-card may fail:

  U-Boot SPL 2024.04-rc4 (Mar 16 2024 - 12:36:12 +0000)
  Trying to boot from MMC2
  mmc_load_image_raw_sector: mmc block read error
  Trying to boot from MMC1
  Card did not respond to voltage select! : -110
  mmc_init: -95, time 12
  spl: mmc init failed with error: -95
  Trying to boot from MMC2
  mmc_load_image_raw_sector: mmc block read error
  SPL: failed to boot from all boot devices (err=-6)
  ### ERROR ### Please RESET the board ###

Fix this by tagging related emmc and sdmmc pinctrl nodes with bootph
props. Also sort and move common nodes shared by all boards to the SoC
u-boot.dtsi.

Imply SPL_PINCTRL and SPL_DM_SEQ_ALIAS to apply correct pinconf before
trying to load FIT from a device.

Move u-boot,spl-boot-order to soc u-boot.dtsi and define both sdmmc and
emmc nodes as fallback.

Also fix boot from eMMC (SD NAND) on ROCK Pi S by using correct pinctrl.

Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>