Add option -fweb for pr47763.c

This case is testing 'web' on ignore naked clobber.
-funroll-loops no longer implies -fweb for powerpc.
So, add -fweb to enable 'web' for this case.

gcc.testsuite/
2019-11-13  Jiufu Guo  <guojiufu@linux.ibm.com>

	PR target/92465
	* gcc.dg/pr47763.c: Add option -fweb.

From-SVN: r278112

gcc/testsuite/ChangeLog

+2019-11-13  Jiufu Guo  <guojiufu@linux.ibm.com>
+
+	PR target/92465
+	* gcc.dg/pr47763.c: Add option -fweb.
+
 2019-11-12  Nathan Sidwell  <nathan@acm.org>
 
 	* g++.dg/cpp0x/using-enum-2.C: Adjust expected error text.

gcc/testsuite/gcc.dg/pr47763.c

 /* { dg-do compile } */
-/* { dg-options "-O2 -funroll-loops -fdump-rtl-web" } */
+/* { dg-options "-O2 -funroll-loops -fweb -fdump-rtl-web" } */
 
 int
 foo()