usage.c: remove reference to busybox.h
*: s/include "busybox.h"/include "libbb.h"

diff --git a/coreutils/cat.c b/coreutils/cat.c
index ed3f336..64e697e 100644
--- a/coreutils/cat.c
+++ b/coreutils/cat.c
@@ -10,7 +10,7 @@
 /* BB_AUDIT SUSv3 compliant */
 /* http://www.opengroup.org/onlinepubs/007904975/utilities/cat.html */
 
-#include "busybox.h"
+#include "libbb.h"
 
 /* This is a NOFORK applet. Be very careful! */