Add missing MODULE_LICENSE tag to oid_registry

[Dave Jones <davej@redhat.com>]

if CONFIG_OID_REGISTRY=m

[  241.094450] oid_registry: module license 'unspecified' taints kernel.

Signed-off-by: Dave Jones <davej@redhat.com>

diff --git a/lib/oid_registry.c b/lib/oid_registry.c
index d8de11f..6eff319 100644
--- a/lib/oid_registry.c
+++ b/lib/oid_registry.c
@@ -9,6 +9,7 @@
  * 2 of the Licence, or (at your option) any later version.
  */
 
+#include <linux/module.h>
 #include <linux/export.h>
 #include <linux/oid_registry.h>
 #include <linux/kernel.h>
@@ -168,3 +169,5 @@ int sprint_OID(enum OID oid, char *buffer, size_t bufsize)
 	return ret;
 }
 EXPORT_SYMBOL_GPL(sprint_OID);
+
+MODULE_LICENSE("GPL");