Unregister pthread_atfork handlers on dlclose()

Change-Id: I326fdf6bb06bed12743f08980b5c69d849c015b8
diff --git a/libc/Android.mk b/libc/Android.mk
index 4a199e7..8ed969f 100644
--- a/libc/Android.mk
+++ b/libc/Android.mk
@@ -63,6 +63,7 @@
     stdio/sprintf.c \
     stdio/stdio.c \
     stdio/stdio_ext.cpp \
+    stdlib/atexit.c \
     stdlib/exit.c \
 
 # Fortify implementations of libc functions.
@@ -481,7 +482,6 @@
     upstream-openbsd/lib/libc/stdio/wprintf.c \
     upstream-openbsd/lib/libc/stdio/wscanf.c \
     upstream-openbsd/lib/libc/stdio/wsetup.c \
-    upstream-openbsd/lib/libc/stdlib/atexit.c \
     upstream-openbsd/lib/libc/stdlib/atoi.c \
     upstream-openbsd/lib/libc/stdlib/atol.c \
     upstream-openbsd/lib/libc/stdlib/atoll.c \