[4.8-specific fixup for the pr12081-1 patch <mikpe@it.uu.se>]

--- gcc-4.8.0/gcc/config/rs6000/rs6000.c.~1~	2013-05-25 10:28:43.494543787 +0200
+++ gcc-4.8.0/gcc/config/rs6000/rs6000.c	2013-05-25 10:41:05.323646639 +0200
@@ -26643,7 +26643,7 @@ rs6000_emit_swdiv_high_precision (rtx ds
   enum machine_mode mode = GET_MODE (dst);
   rtx x0, e0, e1, y1, u0, v0;
   enum insn_code code = optab_handler (smul_optab, mode);
-  gen_2arg_fn_t gen_mul = (gen_2arg_fn_t) GEN_FCN (code);
+  gen_2arg_fn_t gen_mul = (gen_2arg_fn_t) GEN_FCN3 (code);
   rtx one = rs6000_load_constant_and_splat (mode, dconst1);
 
   gcc_assert (code != CODE_FOR_nothing);