make: use the more modern wchar routines, not widec.h

@@ -123,11 +123,11 @@
                     ) {
                         continue;
                 }
                 INIT_STRING_FROM_STACK(value, buffer);          
                 expand_value(p->value, &value, false);
-                if ((length = wslen(value.buffer.start)) >= MAXPATHLEN) {
+                if ((length = wcslen(value.buffer.start)) >= MAXPATHLEN) {
                         mbs = tmp_mbs_buffer = getmem((length + 1) * MB_LEN_MAX);
                         (void) wcstombs(mbs,
                                         value.buffer.start,
                                         (length + 1) * MB_LEN_MAX);
                 } else {