This NAND flash remapping method is used on newer MediaTek devices with NAND
flash.
Signed-off-by: Felix Fietkau <nbd@nbd.name>
(cherry-picked from commit 06382d1af7)
Preparation for supporting BMT on MT7621. Move source files to the files/
subdirectory in order to simplify maintenance
Signed-off-by: Felix Fietkau <nbd@nbd.name>