This commit enables zephyr to configure the FatFs FF_FS_REENTRANT
option and support fs actions from multiple threads.
CONFIG_FS_FATFS_REENTRANT enables the option and provides zephyr
mutex wrappers.
Signed-off-by: Nicola Ochsenbein <Nicola.Ochsenbein@husqvarnagroup.com>
The code moves Zephyr specific code and CMakeLists.txt
under modules/fatfs/.
The commit also adds zephyr_fatfs_config.h header file, that
is now used to override FF_ options of ffconf.h file within
fatfs repository.
Signed-off-by: Dominik Ermel <dominik.ermel@nordicsemi.no>