widl: Make the generated string pointers const as well.

tools/widl/typegen.c

@@ -3348,7 +3348,7 @@ void write_endpoints( FILE *f, const char *prefix, const str_list_t *list )
     const char *p;
 
     /* this should be an array of RPC_PROTSEQ_ENDPOINT but we want const strings */
-    print_file( f, 0, "static const unsigned char * %s__RpcProtseqEndpoint[][2] =\n{\n", prefix );
+    print_file( f, 0, "static const unsigned char * const %s__RpcProtseqEndpoint[][2] =\n{\n", prefix );
     LIST_FOR_EACH_ENTRY( endpoint, list, const struct str_list_entry_t, entry )
     {
         print_file( f, 1, "{ (const unsigned char *)\"" );