Fix ifcvt-4.c to not depend on VRP2 asserts.

The testcase fails if VRP2 is replaced with a non-assert based VRP because it
accidentally depends on specific IL changes when the asserts are removed.  This
removes that dependency.

	gcc/testsuite/
	* gcc.dg/ifcvt-4.c: Adjust.

gcc/testsuite/gcc.dg/ifcvt-4.c

@@ -13,8 +13,7 @@ foo (word x, word y, word a)
   word i = x;
   word j = y;
   /* Try to make taking the branch likely.  */
-  __builtin_expect (x > y, 1);
-  if (x > y)
+  if (__builtin_expect (x > y, 0))
     {
       i = a;
       j = i;