[BUG] config: disable 'option httplog' on TCP proxies

Gabriel Sosa reported that logs were appearing with BADREQ when
'option httplog' was used with a TCP proxy (eg: inherited via a
default instance). This patch detects it and falls back to tcplog
after emitting a warning.
(cherry picked from commit 5f0bd6537f8b56b643ef485d7a3c96d996d9b01a)
diff --git a/src/proxy.c b/src/proxy.c
index 181cdd8..38eb2be 100644
--- a/src/proxy.c
+++ b/src/proxy.c
@@ -391,6 +391,11 @@
 		Warning("config : Layer 7 hash not possible for %s '%s' (needs 'mode http'). Falling back to round robin.\n",
 			proxy_type_str(curproxy), curproxy->id);
 	}
+	if (curproxy->to_log & (LW_REQ | LW_RESP)) {
+		curproxy->to_log &= ~(LW_REQ | LW_RESP);
+		Warning("config : 'option httplog' not usable with %s '%s' (needs 'mode http'). Falling back to 'option tcplog'.\n",
+			proxy_type_str(curproxy), curproxy->id);
+	}
 	return 0;
 }