[cleanup] Convert XMALLOC/memset to XCALLOC

Simple conversion of XMALLOC/memset to XCALLOC
diff --git a/ospfclient/ospf_apiclient.c b/ospfclient/ospf_apiclient.c
index 64b8312..ed7ca94 100644
--- a/ospfclient/ospf_apiclient.c
+++ b/ospfclient/ospf_apiclient.c
@@ -259,8 +259,7 @@
   close (async_server_sock);
 
   /* Create new client-side instance */
-  new = XMALLOC (MTYPE_OSPF_APICLIENT, sizeof (struct ospf_apiclient));
-  memset (new, 0, sizeof (struct ospf_apiclient));
+  new = XCALLOC (MTYPE_OSPF_APICLIENT, sizeof (struct ospf_apiclient));
 
   /* Initialize socket descriptors for sync and async channels */
   new->fd_sync = fd1;