utils: Remove leftover g_chmod()

The file has set the attributes after commit c6903ab,
thus this is not needed.

If it was meant to set the executable flag on the parent directory, then it
is not needed either, at least according to my tests. The `path_dest` points
to the installed file here, not to the parent directory.

Closes #681

src/as-utils.c

@@ -2496,7 +2496,6 @@ as_utils_install_metadata_file_internal (const gchar *filename,
 			return FALSE;
 	}
 
-	g_chmod (path_dest, 0755);
 	return TRUE;
 }