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

diff --git a/procps/fuser.c b/procps/fuser.c
index 40789dd..f65b05d 100644
--- a/procps/fuser.c
+++ b/procps/fuser.c
@@ -8,7 +8,7 @@
  * GNU Library General Public License
  */
 
-#include "busybox.h"
+#include "libbb.h"
 
 #define FUSER_PROC_DIR "/proc"
 #define FUSER_MAX_LINE 255