mboxd: Rename flash files

Change-Id: Icfe9d61775a198c5a0f8227bf5d6c4b7f11aeec3
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
diff --git a/mboxd_windows.c b/mboxd_windows.c
index 6a14e68..200b205 100644
--- a/mboxd_windows.c
+++ b/mboxd_windows.c
@@ -29,7 +29,7 @@
 #include "common.h"
 #include "mboxd_msg.h"
 #include "mboxd_windows.h"
-#include "mboxd_flash.h"
+#include "flash.h"
 
 /* Initialisation Functions */