[qca-nss-ecm] if/def multicast specific function.

Encapsulate the multicast specific function with the
ECM_MULTICAST_ENABLE flag.

Change-Id: I791bf92263778851ba8b7957fcfac46e6341b85e
Signed-off-by: Murat Sezgin <msezgin@codeaurora.org>
diff --git a/ecm_interface.c b/ecm_interface.c
index 0bba256..85110d5 100644
--- a/ecm_interface.c
+++ b/ecm_interface.c
@@ -3069,7 +3069,6 @@
 	return ii_cnt;
 }
 EXPORT_SYMBOL(ecm_interface_multicast_heirarchy_construct_bridged);
-#endif
 
 /*
  * ecm_interface_multicast_get_next_node_mac_address()
@@ -3104,6 +3103,7 @@
 
 	return true;
 }
+#endif
 
 /*
  * ecm_interface_get_next_node_mac_address()