[MEDIUM] make the unix stats sockets use the generic session handler

process_session() is now ready to handle unix stats sockets. This
first step works and old code has not been removed. A cleanup is
required. The stats handler is not unix socket-centric anymore and
should move to dumpstats.c.
diff --git a/src/dumpstats.c b/src/dumpstats.c
index 0615366..2683b52 100644
--- a/src/dumpstats.c
+++ b/src/dumpstats.c
@@ -106,7 +106,7 @@
 		global.stats_sock.state = LI_INIT;
 		global.stats_sock.options = LI_O_NONE;
 		global.stats_sock.accept = uxst_event_accept;
-		global.stats_sock.handler = uxst_process_session;
+		global.stats_sock.handler = process_session;
 		global.stats_sock.analysers = AN_REQ_UNIX_STATS;
 		global.stats_sock.private = global.stats_fe; /* must point to the frontend */