f2fs: remove dead code f2fs_check_acl

The macro f2fs_check_acl is defined but never used since
the initial commit, this patch removes the code that has
been dead for several years.
Signed-off-by: Tiezhu Yang <kernelpatch@126.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/acl.h

@@ -41,7 +41,6 @@ extern int f2fs_set_acl(struct inode *, struct posix_acl *, int);
 extern int f2fs_init_acl(struct inode *, struct inode *, struct page *,
 							struct page *);
 #else
-#define f2fs_check_acl	NULL
 #define f2fs_get_acl	NULL
 #define f2fs_set_acl	NULL