add a hack to fix debug-info tests under gdb 7.7

Author: thestinger

src/test/debug-info/basic-types-metadata.rs

@@ -45,7 +45,7 @@
 // debugger:whatis f64
 // check:type = f64
 // debugger:info functions _yyy
-// check:[...]![...]_yyy()();
+// check:[...]![...]_yyy([...])([...]);
 // debugger:detach
 // debugger:quit