drivers/char/ftape/lowlevel/ftape-buffer.c should #include "../lowlevel/ftape-buffer.h"

Every file should #include the headers containing the prototypes for
it's global functions.

Signed-off-by: Adrian Bunk <bunk@stusta.de>
diff --git a/drivers/char/ftape/lowlevel/ftape-buffer.c b/drivers/char/ftape/lowlevel/ftape-buffer.c
index 54af20c..c706ff1 100644
--- a/drivers/char/ftape/lowlevel/ftape-buffer.c
+++ b/drivers/char/ftape/lowlevel/ftape-buffer.c
@@ -33,6 +33,7 @@
 #include "../lowlevel/ftape-rw.h"
 #include "../lowlevel/ftape-read.h"
 #include "../lowlevel/ftape-tracing.h"
+#include "../lowlevel/ftape-buffer.h"
 
 /*  DMA'able memory allocation stuff.
  */