5045 use atomic_{inc,dec}_* instead of atomic_add_*

@@ -771,11 +771,11 @@
                         frm->frm_eport->eport_free_netb(frm->frm_netb);
                         frm->frm_eport->eport_release_frame(frm);
                         break;
 
                 case AE_EVENT_PORT:
-                        atomic_add_32(&ss->ss_port_event_counter, -1);
+                        atomic_dec_32(&ss->ss_port_event_counter);
                         /* FALLTHROUGH */
 
                 case AE_EVENT_RESET:
                         kmem_free(ae, sizeof (fcoei_event_t));
                         break;