mtd: Add module.h to drivers users that were implicitly using it.

We are cleaning up the implicit presence of module.h that these
drivers are taking advantage of.  Fix them in advance of the
cleanup operation.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/drivers/mtd/rfd_ftl.c b/drivers/mtd/rfd_ftl.c
index cc4d180..73ae217 100644
--- a/drivers/mtd/rfd_ftl.c
+++ b/drivers/mtd/rfd_ftl.c
@@ -18,6 +18,7 @@
 #include <linux/vmalloc.h>
 #include <linux/slab.h>
 #include <linux/jiffies.h>
+#include <linux/module.h>
 
 #include <asm/types.h>