S/390: Fix 64 bit sibcall

This fixes a problem revealed during the split-stack work:
https://gcc.gnu.org/ml/gcc-patches/2016-02/msg00322.html

gcc/ChangeLog:

2016-02-05  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>

	* config/s390/s390.c (s390_emit_call): Add missing 64 bit check.

From-SVN: r233169

gcc/ChangeLog

 2016-02-05  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>
 
+	* config/s390/s390.c (s390_emit_call): Add missing 64 bit check.
+
+2016-02-05  Andreas Krebbel  <krebbel@linux.vnet.ibm.com>
+
 	PR target/69625
 	* config/s390/s390.c (SAVE_SLOT_NONE, SAVE_SLOT_STACK): New
 	defines.

gcc/config/s390/s390.c

@@ -12507,7 +12507,7 @@ s390_emit_call (rtx addr_location, rtx tls_call, rtx result_reg,
          replace the symbol itself with the PLT stub.  */
       if (flag_pic && !SYMBOL_REF_LOCAL_P (addr_location))
         {
-	  if (retaddr_reg != NULL_RTX)
+	  if (TARGET_64BIT || retaddr_reg != NULL_RTX)
 	    {
 	      addr_location = gen_rtx_UNSPEC (Pmode,
 					      gen_rtvec (1, addr_location),