Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6

Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs fixes from Steve French:
 "A small set of cifs fixes.

  I am still reviewing some more, recently submitted SMB3 fixes, but
  these three are small and safe and ready now"

* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
  cifs: fix erroneous return value
  cifs: fix potential overflow in cifs_compose_mount_options
  cifs: remove redundant check for null string pointer