Use <> instead of "" for external header includes

Libraries and system headers should be included with <> instead of "".
This makes a great difference for the automatic dependency tracking.

Signed-off-by: Joachim Nilsson <troglobit@gmail.com>

tty.c

@@ -24,12 +24,12 @@
 
 #include <signal.h>
 #include <sys/wait.h>
+#include <lite/lite.h>
 
 #include "config.h"		/* Generated by configure script */
 #include "finit.h"
 #include "conf.h"
 #include "helpers.h"
-#include "lite/lite.h"
 #include "tty.h"
 
 LIST_HEAD(, tty_node) tty_list = LIST_HEAD_INITIALIZER();