[Bug target/20819] Enable -mlong_calls for IA64 to use brl.call

[pinskia at gcc dot gnu dot org]

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
  GCC build triplet|ia64-redhat-linux           |
   GCC host triplet|ia64-redhat-linux           |
 GCC target triplet|ia64-redhat-linux           |ia64-*-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20819