luatelnet: don't replace \r by extra \n

It's useless and create bogus empty commands, that output ugly blank
lines and crap during login
(cherry picked from commit a94688f91336176d32649824369dc9d9bde8d126)
Signed-off-by: Pierre Ynard <linkfanel@yahoo.fr>

share/lua/intf/telnet.lua

@@ -181,7 +181,7 @@ while not vlc.misc.should_die() do
 
     -- Handle reads
     for _, client in pairs(r) do
-        local str = client.cmds .. string.gsub(client:recv(1000), "\r", "\n")
+        local str = client.cmds .. client:recv(1000)
 
         if not str then -- the telnet client program has leave
             client.cmds = "quit"