bgpd: use XCALLOC to allocate bgpd damp array

* bgpd: (bgp_damp_parameter_set) The BGP reuse_index is not initialized
  properly.  This would cause sporadic crash when disabling dampening.  Use
  XCALLOC correctly and the right size array is initialized and no memset is
  needed.
diff --git a/bgpd/bgp_damp.c b/bgpd/bgp_damp.c
index ba059f8..a513883 100644
--- a/bgpd/bgp_damp.c
+++ b/bgpd/bgp_damp.c
@@ -407,14 +407,10 @@
   damp->reuse_list = XCALLOC (MTYPE_BGP_DAMP_ARRAY, 
 			      damp->reuse_list_size 
 			      * sizeof (struct bgp_reuse_node *));
-  memset (damp->reuse_list, 0x00, 
-          damp->reuse_list_size * sizeof (struct bgp_reuse_node *));  
 
   /* Reuse-array computations */
-  damp->reuse_index = XMALLOC (MTYPE_BGP_DAMP_ARRAY, 
+  damp->reuse_index = XCALLOC (MTYPE_BGP_DAMP_ARRAY,
 			       sizeof(int) * damp->reuse_index_size);
-  memset (damp->reuse_index, 0x00,
-          damp->reuse_list_size * sizeof (int));
 
   reuse_max_ratio = (double)damp->ceiling/damp->reuse_limit;
   j = (exp((double)damp->max_suppress_time/damp->half_life) * log10(2.0));