MEDIUM: thread/spoe: Make the SPOE thread-safe

Because there is not migration mechanism yet, all runtime information about an
SPOE agent are thread-local and async exchanges with agents are disabled when we
have serveral threads. Howerver, pipelining is still available. So for now, the
thread part of the SPOE is pretty simple.
diff --git a/include/common/hathreads.h b/include/common/hathreads.h
index 774fe7b..39d8220 100644
--- a/include/common/hathreads.h
+++ b/include/common/hathreads.h
@@ -167,6 +167,7 @@
 	COMP_POOL_LOCK,
 	LUA_LOCK,
 	NOTIF_LOCK,
+	SPOE_APPLET_LOCK,
 	LOCK_LABELS
 };
 struct lock_stat {
@@ -255,7 +256,7 @@
 					   "UPDATED_SERVERS", "LBPRM", "SIGNALS", "STK_TABLE", "STK_SESS",
 					   "APPLETS", "PEER", "BUF_WQ", "STREAMS", "SSL", "SSL_GEN_CERTS",
 					   "PATREF", "PATEXP", "PATLRU", "VARS", "COMP_POOL", "LUA",
-					   "NOTIF" };
+					   "NOTIF", "SPOE_APPLET" };
 	int lbl;
 
 	for (lbl = 0; lbl < LOCK_LABELS; lbl++) {