staging: vt6656: fix bad symbol declaration

With sparse, the following error appears :
CHECK drivers/staging/vt6656/aes_ccmp.c
drivers/staging/vt6656/aes_ccmp.c:221:6: warning: symbol 'AESbGenCCMP' was not declared. Should it be static?

Add correct include header in order to have function declaration.

---
 drivers/staging/vt6656/aes_ccmp.c |    1 +
 1 file changed, 1 insertion(+)

index e2bfa8d..a9d5168 100644
@@ -32,6 +32,7 @@
 
 #include "device.h"
 #include "80211hdr.h"
+#include "aes_ccmp.h"
 
 /*
  * SBOX Table

1.7.10.4