Fix accessing the environment in case no OS is installed on the flash
media selected for boot as this is possible when booting initramfs.
In case of relying on the device specified to be mounted as rootfs to
be present, rather just use the kernel cmdline 'root' variable as a
hint to decide where to read/write the U-Boot environment.
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Create new mediatek_filogic file and add entries for environment on
MMC, UBI and NOR for the Bananapi BPi-R3.
Signed-off-by: Daniel Golle <daniel@makrotopia.org>