mmc: Add module.h to drivers/mmc users assuming implicit presence.

We are cleaning up the implicit presence of module.h; these guys are
some of the people who just assume it will be there.  Call it out
explitly for those that really need it.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
diff --git a/drivers/mmc/card/mmc_test.c b/drivers/mmc/card/mmc_test.c
index 9cdce63..d8705ad 100644
--- a/drivers/mmc/card/mmc_test.c
+++ b/drivers/mmc/card/mmc_test.c
@@ -22,6 +22,7 @@
 #include <linux/debugfs.h>
 #include <linux/uaccess.h>
 #include <linux/seq_file.h>
+#include <linux/module.h>
 
 #define RESULT_OK		0
 #define RESULT_FAIL		1