在进行https握手时，会有小概率在进行密钥协商前，tcp流卡住，导至不能有效timeout行为 (#1842)

lualib/http/httpc.lua

@@ -83,9 +83,6 @@ local function connect(host, timeout)
 	end
 	-- print("protocol hostname port", protocol, hostname, port)
 	local interface = gen_interface(protocol, fd, hostname)
-	if interface.init then
-		interface.init()
-	end
 	if timeout then
 		skynet.timeout(timeout, function()
 			if not interface.finish then
@@ -93,6 +90,9 @@ local function connect(host, timeout)
 			end
 		end)
 	end
+	if interface.init then
+		interface.init()
+	end
 	return fd, interface, host
 end