[Patch testsuite] Skip gcc.dg/ifcvt-4.c for targets on which it may not work

gcc/testsuite/

	PR testsuite/68232
	* gcc.dg/ifcvt-4.c: Skip for arm*-*-* and powerpc64le*-*-*.

From-SVN: r231929

gcc/testsuite/ChangeLog

+2015-12-23  James Greenhalgh  <james.greenhalgh@arm.com>
+
+	PR testsuite/68232
+	* gcc.dg/ifcvt-4.c: Skip for arm*-*-* and powerpc64le*-*-*.
+
 2015-12-23  Nathan Sidwell  <nathan@acm.org>
 
 	* gcc.dg/alias-15.c: New. 

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

 /* { dg-options "-fdump-rtl-ce1 -O2" } */
+/* { dg-skip-if "Multiple set if-conversion not guaranteed on all subtargets" { "arm*-*-* powerpc64le*-*-*" } {"*"} { "" } }  */
+
 int
 foo (int x, int y, int a)
 {