remove code duplication between telnet-client / telnet-client-ipa

We now simply use the original telnet-client.c with one small callback
into the ipaccess authentication layer
diff --git a/util/telnet-client.c b/util/telnet-client.c
index 5565656..f2fcedb 100644
--- a/util/telnet-client.c
+++ b/util/telnet-client.c
@@ -135,6 +135,8 @@
 	}
 }
 
+extern int ipaccess_telnet_auth(int sock);
+
 int main(int argc, char **argv) {
 	char buffer[512];
 	int rs;
@@ -184,6 +186,10 @@
 	/* free address lookup info */
 	freeaddrinfo(ai);
 
+#if NANO_BTS_CLI_CLIENT
+	ipaccess_telnet_auth(sock);
+#endif
+
 	/* get current terminal settings, set raw mode, make sure we
 	 * register atexit handler to restore terminal settings
 	 */