[cleanup] Convert XMALLOC/memset to XCALLOC

Simple conversion of XMALLOC/memset to XCALLOC
diff --git a/bgpd/bgp_aspath.c b/bgpd/bgp_aspath.c
index d0d621c..5881abe 100644
--- a/bgpd/bgp_aspath.c
+++ b/bgpd/bgp_aspath.c
@@ -322,11 +322,7 @@
 static struct aspath *
 aspath_new (void)
 {
-  struct aspath *aspath;
-
-  aspath = XMALLOC (MTYPE_AS_PATH, sizeof (struct aspath));
-  memset (aspath, 0, sizeof (struct aspath));
-  return aspath;
+  return XCALLOC (MTYPE_AS_PATH, sizeof (struct aspath));
 }
 
 /* Free AS path structure. */