rtc: Add module.h to implicit users in drivers/rtc

The module.h was implicitly everywhere, but when we clean
that up, the implicit users will compile fail; fix them up
in advance.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/drivers/rtc/rtc-ds1553.c b/drivers/rtc/rtc-ds1553.c
index fee41b9..1350029 100644
--- a/drivers/rtc/rtc-ds1553.c
+++ b/drivers/rtc/rtc-ds1553.c
@@ -18,6 +18,7 @@
 #include <linux/rtc.h>
 #include <linux/platform_device.h>
 #include <linux/io.h>
+#include <linux/module.h>
 
 #define DRV_VERSION "0.3"