pkg/fatfs: bump to r0.15

- Changed user provided synchronization functions in order to completely eliminate the platform dependency from FatFs code.
 - Fixed a potential error in f_mount when FF_FS_REENTRANT.
 - Fixed file lock control FF_FS_LOCK is not mutal excluded when FF_FS_REENTRANT && FF_VOLUMES > 1 is true.
 - Fixed f_mkfs creates broken exFAT volume when the size of volume is >= 2^32 sectors.
 - Fixed string functions cannot write the unicode characters not in BMP when FF_LFN_UNICODE == 2 (UTF-8).
 - Fixed a compatibility issue in identification of GPT header.

pkg/fatfs/Makefile

@@ -2,8 +2,8 @@ PKG_NAME=fatfs
 # upstream server is very unreliable, instead host the extracted
 # .zip file on GitHub and apply only the upstream patches
 PKG_URL=https://github.com/RIOT-OS/FatFS
-# r0.14b
-PKG_VERSION=246c97b1eb7f1900eb00d5ed7e3bf4cdb4558039
+# r0.15
+PKG_VERSION=dab28e92fb4a2bea604771ede126251b9d35692a
 PKG_LICENSE=BSD-1-Clause
 
 include $(RIOTBASE)/pkg/pkg.mk

pkg/fatfs/vendor/include/ffconf.h

@@ -2,7 +2,7 @@
 /  FatFs - Configuration file
 /---------------------------------------------------------------------------*/
 
-#define FFCONF_DEF	86631	/* Revision ID */
+#define FFCONF_DEF	80286	/* Revision ID */
 
 /*---------------------------------------------------------------------------/
 / Function Configurations