MINOR: mworker: support a configurable maximum number of reloads

This patch implements a new global parameter for the master-worker mode.
When setting the mworker-max-reloads value, a worker receive a SIGTERM
if its number of reloads is greater than this value.
diff --git a/src/haproxy.c b/src/haproxy.c
index 8ab0c2e..4c37125 100644
--- a/src/haproxy.c
+++ b/src/haproxy.c
@@ -2780,6 +2780,10 @@
 	if (nb_oldpids && !(global.mode & MODE_MWORKER_WAIT))
 		nb_oldpids = tell_old_pids(oldpids_sig);
 
+	/* send a SIGTERM to workers who have a too high reloads number  */
+	if ((global.mode & MODE_MWORKER) && !(global.mode & MODE_MWORKER_WAIT))
+		mworker_kill_max_reloads(SIGTERM);
+
 	if ((getenv("HAPROXY_MWORKER_REEXEC") == NULL)) {
 		nb_oldpids = 0;
 		free(oldpids);