CONFIG_SYS_FSL_ESDHC_LE means ESDHC IP is in little-endian mode.
CONFIG_SYS_FSL_ESDHC_BE means ESDHC IP is in big-endian mode.
CONFIG_SYS_FSL_ESDHC_FORCE_VSELECT forces to run at 1.8V.

Accessing ESDHC registers can be determined by ESDHC IP's endian
mode or processor's endian mode.
