[PATCH][xtensa] Remove unused variable

[Chung-Lin Tang]

Hi Sterling,
the last thread pointer builtin changes left an unused 'arg' variable in
xtensa_expand_builtin(), which triggered a new warning. Thanks to
Jan-Benedict for testing this. Attached patch was committed as obvious.

Thanks,
Chung-Lin

        * config/xtensa/xtensa.c (xtensa_expand_builtin): Remove unused
        'arg' variable.

Index: config/xtensa/xtensa.c
===================================================================
--- config/xtensa/xtensa.c      (revision 192647)
+++ config/xtensa/xtensa.c      (working copy)
@@ -3133,7 +3133,6 @@ xtensa_expand_builtin (tree exp, rtx target,
 {
   tree fndecl = TREE_OPERAND (CALL_EXPR_FN (exp), 0);
   unsigned int fcode = DECL_FUNCTION_CODE (fndecl);
-  rtx arg;
 
   switch (fcode)
     {