Fix a potential infinite loop during thread exit.

Fix malloc_tsd_dalloc() to bypass tcache when dallocating, so that there
is no danger of causing tcache reincarnation during thread exit.
Whether this infinite loop occurs depends on the pthreads TSD
implementation; it is known to occur on Solaris.

Submitted by Markus Eberspächer.

src/tsd.c

@@ -21,7 +21,7 @@ void
 malloc_tsd_dalloc(void *wrapper)
 {
 
-	idalloc(wrapper);
+	idallocx(wrapper, false);
 }
 
 void