mmc: Checks EXT_CSD_PARTITION_SETTING_COMPLETED before partitions computation
Checks EXT_CSD_PARTITION_SETTING_COMPLETED bit before
computing enhanced user area offset and size, and
adding mmc general purpose partitions. The two needs
EXT_CSD_PARTITION_SETTING_COMPLETED bit be set to be
valid (as described in JEDEC standard).
Warn user in case of misconfiguration.