Staging: lustre: Remove extern from function declaration

Functions have the extern storage class specifier by default,
so this keyword can be removed.
Signed-off-by: Vatika Harlalka <vatikaharlalka@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/lustre/lustre/ldlm/ldlm_internal.h

@@ -211,9 +211,9 @@ struct ldlm_state {
 /* interval tree, for LDLM_EXTENT. */
 extern struct kmem_cache *ldlm_interval_slab; /* slab cache for ldlm_interval */
 extern void ldlm_interval_attach(struct ldlm_interval *n, struct ldlm_lock *l);
-extern struct ldlm_interval *ldlm_interval_detach(struct ldlm_lock *l);
-extern struct ldlm_interval *ldlm_interval_alloc(struct ldlm_lock *lock);
-extern void ldlm_interval_free(struct ldlm_interval *node);
+struct ldlm_interval *ldlm_interval_detach(struct ldlm_lock *l);
+struct ldlm_interval *ldlm_interval_alloc(struct ldlm_lock *lock);
+void ldlm_interval_free(struct ldlm_interval *node);
 /* this function must be called with res lock held */
 static inline struct ldlm_extent *
 ldlm_interval_extent(struct ldlm_interval *node)