MINOR: session: make use of session_new() when creating a new session

It's better than open-coding it.
diff --git a/src/session.c b/src/session.c
index 5580d4f..7f4e45e 100644
--- a/src/session.c
+++ b/src/session.c
@@ -117,7 +117,7 @@
 	if (conn_xprt_init(cli_conn) < 0)
 		goto out_free_conn;
 
-	sess = pool_alloc2(pool2_session);
+	sess = session_new(p, l, &cli_conn->obj_type);
 	if (!sess)
 		goto out_free_conn;
 
@@ -128,13 +128,6 @@
 
 	proxy_inc_fe_conn_ctr(l, p);
 
-	sess->listener = l;
-	sess->fe  = p;
-	sess->origin = &cli_conn->obj_type;
-	sess->accept_date = date; /* user-visible date for logging */
-	sess->tv_accept   = now;  /* corrected date for internal use */
-	memset(sess->stkctr, 0, sizeof(sess->stkctr));
-
 	/* now evaluate the tcp-request layer4 rules. We only need a session
 	 * and no stream for these rules.
 	 */