drivers/exfat: add Samsung's open source exFat module version 1.2.4

Signed-off-by: Paul Reioux <reioux@gmail.com>
Change-Id: I66404bdc5da3ce46b4a6a3cd6694c3f978a4b415
Merge "drivers/exfat: add Samsung's open source exFat module version 1.2.4" into du44