BUG/MINOR: server: Missing calloc return value check in srv_parse_source

Two calloc calls were not checked in the srv_parse_source function.
Considering that this function could be called at runtime through a
dynamic server creation via the CLI, this could lead to an unfortunate
crash.

It was raised in GitHub issue #1233.
It could be backported to all stable branches even though the runtime
crash could only happen on branches where dynamic server creation is
possible.

(cherry picked from commit f1800e64ef2428747e696b0ef2f78ab05a116dcc)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
diff --git a/src/server.c b/src/server.c
index 49bd545..be4e6e1 100644
--- a/src/server.c
+++ b/src/server.c
@@ -1060,6 +1060,10 @@
 		int i;
 
 		newsrv->conn_src.sport_range = port_range_alloc_range(port_high - port_low + 1);
+		if (!newsrv->conn_src.sport_range) {
+			ha_alert("Server '%s': Out of memory (sport_range)\n", args[0]);
+			goto err;
+		}
 		for (i = 0; i < newsrv->conn_src.sport_range->size; i++)
 			newsrv->conn_src.sport_range->ports[i] = port_low + i;
 	}
@@ -1096,6 +1100,10 @@
 				newsrv->conn_src.opts |= CO_SRC_TPROXY_DYN;
 				free(newsrv->conn_src.bind_hdr_name);
 				newsrv->conn_src.bind_hdr_name = calloc(1, end - name + 1);
+				if (!newsrv->conn_src.bind_hdr_name) {
+					ha_alert("Server '%s': Out of memory (bind_hdr_name)\n", args[0]);
+					goto err;
+				}
 				newsrv->conn_src.bind_hdr_len = end - name;
 				memcpy(newsrv->conn_src.bind_hdr_name, name, end - name);
 				newsrv->conn_src.bind_hdr_name[end - name] = '\0';