Test for AltiVec function vec_ld, passing a pointer to const vector.

Approved by Aldy Hernandez.

From-SVN: r81716

gcc/testsuite/g++.dg/ext/altivec-9.C

+/* Test for AltiVec function vec_ld, passing a pointer to const vector */
+/* { dg-do compile { target powerpc*-*-* } } */
+/* { dg-options "-maltivec" } */
+
+#include <altivec.h>
+
+typedef vector unsigned char vuc_t;
+const vuc_t* p;
+vector unsigned char test_vec_ld()
+{
+        return vec_ld(0,p);
+}
+