update 1.1.2 to 1.1.3
CHANGES :
- mkfs.exfat: ensure that the cluster size is greater than or equal than the sector size.
- mkfs.exfat: replace lseek() + write() with pwrite().
BUG FIXES :
- mkfs.exfat: prevent an integer overflow when computing the FAT length.
- fsck.exfat: fix a double free memory error.