[cleanup] Convert XMALLOC/memset to XCALLOC

Simple conversion of XMALLOC/memset to XCALLOC
diff --git a/lib/keychain.c b/lib/keychain.c
index 10928b1..af0a1d7 100644
--- a/lib/keychain.c
+++ b/lib/keychain.c
@@ -31,10 +31,7 @@
 static struct keychain *
 keychain_new (void)
 {
-  struct keychain *new;
-  new = XMALLOC (MTYPE_KEYCHAIN, sizeof (struct keychain));
-  memset (new, 0, sizeof (struct keychain));
-  return new;
+  return XCALLOC (MTYPE_KEYCHAIN, sizeof (struct keychain));
 }
 
 static void
@@ -46,10 +43,7 @@
 static struct key *
 key_new (void)
 {
-  struct key *new;
-  new = XMALLOC (MTYPE_KEY, sizeof (struct key));
-  memset (new, 0, sizeof (struct key));
-  return new;
+  return XCALLOC (MTYPE_KEY, sizeof (struct key));
 }
 
 static void