daemon: fix build with musl

musl requires the ttydefaults.h to be included explicitly for CEOF.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
---

diff -Nuar daemon-0.6.4-orig/daemon.c daemon-0.6.4/daemon.c
--- daemon-0.6.4-orig/daemon.c	2010-06-12 16:37:00.000000000 +0300
+++ daemon-0.6.4/daemon.c	2017-05-01 22:02:17.721413468 +0300
@@ -864,6 +864,7 @@
 #ifdef _RESTORE_POSIX_SOURCE
 #define _POSIX_SOURCE
 #endif
+#include <sys/ttydefaults.h>
 #include <dirent.h>
 #include <sys/wait.h>
 #include <sys/stat.h>