hid: Fix up files needing export.h for EXPORT_SYMBOL

With module.h being implicitly everywhere via device.h, the absence
of explicitly including something for EXPORT_SYMBOL went unnoticed.
Since we are heading to fix things up and clean module.h from the
device.h file, we need to explicitly include these files now.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/drivers/hid/hid-debug.c b/drivers/hid/hid-debug.c
index 9a243ca..ee80d73 100644
--- a/drivers/hid/hid-debug.c
+++ b/drivers/hid/hid-debug.c
@@ -31,6 +31,7 @@
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>
 #include <linux/sched.h>
+#include <linux/export.h>
 #include <linux/slab.h>
 #include <linux/uaccess.h>
 #include <linux/poll.h>