IB: Make needlessly global ib_mad_cache static

Signed-off-by: Roland Dreier <rolandd@cisco.com>

drivers/infiniband/core/mad.c

@@ -45,8 +45,7 @@ MODULE_DESCRIPTION("kernel IB MAD API");
 MODULE_AUTHOR("Hal Rosenstock");
 MODULE_AUTHOR("Sean Hefty");
 
-
-kmem_cache_t *ib_mad_cache;
+static kmem_cache_t *ib_mad_cache;
 
 static struct list_head ib_mad_port_list;
 static u32 ib_mad_client_id = 0;

drivers/infiniband/core/mad_priv.h

@@ -212,8 +212,6 @@ struct ib_mad_port_private {
 	struct ib_mad_qp_info qp_info[IB_MAD_QPS_CORE];
 };
 
-extern kmem_cache_t *ib_mad_cache;
-
 int ib_send_mad(struct ib_mad_send_wr_private *mad_send_wr);
 
 struct ib_mad_send_wr_private *