Cygwin: posix timers: allocate timer_tracker on system heap.

Allocating on the cygheap would copy information of the tracker into
the child process.  A forked child knows the timer id and could simply
still access the (free'd but still valid) timer_tracker on the heap,
which is dangerous and very certainly doesn't reflect POSIX semantics.

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>

winsup/cygwin/cygheap_malloc.h

@@ -34,8 +34,7 @@ enum cygheap_types
   HEAP_2_DLL,
   HEAP_MMAP,
   HEAP_2_MAX = 200,
-  HEAP_3_FHANDLER,
-  HEAP_3_TIMER
+  HEAP_3_FHANDLER
 };
 
 extern "C" {