Fix ssa-dse-26.c

Add missing -fno-short-enums to ensure this test passes on arm-none-eabi
which uses short enums.

    gcc/testsuite/
	* gcc.dg/tree-ssa/ssa-dse-26.c (dg-options): Add -fno-short-enums.

From-SVN: r253540

gcc/testsuite/ChangeLog

+2017-10-09  Wilco Dijkstra  <wdijkstr@arm.com>
+
+	* gcc.dg/tree-ssa/ssa-dse-26.c (dg-options): Add -fno-short-enums.
+
 2017-10-09  Tom de Vries  <tom@codesourcery.com>
 
 	* gcc.dg/cold-1.c (foo1): Fix warning line number.  Make warning line

gcc/testsuite/gcc.dg/tree-ssa/ssa-dse-26.c

 /* { dg-do compile } */
-/* { dg-options "-O2 -fdump-tree-dse1-details" } */
+/* { dg-options "-O2 -fdump-tree-dse1-details -fno-short-enums" } */
 
 enum constraint_expr_type
 {
@@ -30,4 +30,3 @@ constraint_equal (struct constraint a, struct constraint b)
 }
 
 /* { dg-final { scan-tree-dump-times "Deleted dead store" 2 "dse1" } } */
-