staging:lustre: Fix externs should be avoided in .c files warning

Fix the checkpatch.pl warning 'externs should be avoided in .c files' in
lustre/lov.
Signed-off-by: Dulshani Gunawardhana <dulshani.gunawardhana89@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/lov/lov_dev.c

@@ -44,6 +44,8 @@
 #include <obd_class.h>
 
 #include "lov_cl_internal.h"
+#include "lov_internal.h"
+
 
 struct kmem_cache *lov_lock_kmem;
 struct kmem_cache *lov_object_kmem;

drivers/staging/lustre/lustre/lov/lov_internal.h

@@ -89,6 +89,8 @@ struct lov_request_set {
 
 extern struct kmem_cache *lov_oinfo_slab;
 
+extern struct lu_kmem_descr lov_caches[];
+
 void lov_finish_set(struct lov_request_set *set);
 
 static inline void lov_get_reqset(struct lov_request_set *set)

drivers/staging/lustre/lustre/lov/lov_obd.c

@@ -2823,8 +2823,6 @@ struct obd_ops lov_obd_ops = {
 
 struct kmem_cache *lov_oinfo_slab;
 
-extern struct lu_kmem_descr lov_caches[];
-
 int __init lov_init(void)
 {
 	struct lprocfs_static_vars lvars = { 0 };