fs/handle.c - fix up kerneldoc

When building with W=1, we get some kerneldoc warnings:

  CC      fs/fhandle.o
fs/fhandle.c:259: warning: Function parameter or member 'flags' not described in 'sys_open_by_handle_at'
fs/fhandle.c:259: warning: Excess function parameter 'flag' description in 'sys_open_by_handle_at'

Fix the typo that caused it.
Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/fhandle.c

@@ -246,7 +246,7 @@ static long do_handle_open(int mountdirfd, struct file_handle __user *ufh,
  * sys_open_by_handle_at: Open the file handle
  * @mountdirfd: directory file descriptor
  * @handle: file handle to be opened
- * @flag: open flags.
+ * @flags: open flags.
  *
  * @mountdirfd indicate the directory file descriptor
  * of the mount point. file handle is decoded relative