TOS bits != DSCP

We have VTY options that allow to set the DSCP value.  However, we
then call a function to set the TOS bits in the kernel.  This is
very wrong.  The DSCP is only the upper 6 bits of the 8-bit TOS
value, and hence we are mussing that translation.

As libosmocore now has a helper function osmo_sock_set_dscp(),
let's make use of it and don't care about the low-level details.

However, this means we need to finally remove the deprecated
alias for "rtp ip-tos <0-255>".

Closes: OS#5137
Change-Id: I9c18c90273be97aedd2ad212b82f650e35c32851
Depends: libosmocore.git Ia4ba389a5b7e3e9d5f17a742a900d6fd68c08e40
diff --git a/src/libosmo-mgcp/mgcp_vty.c b/src/libosmo-mgcp/mgcp_vty.c
index 9ad8c24..6b180ef 100644
--- a/src/libosmo-mgcp/mgcp_vty.c
+++ b/src/libosmo-mgcp/mgcp_vty.c
@@ -579,19 +579,15 @@
 DEFUN_USRATTR(cfg_mgcp_rtp_ip_dscp,
 	      cfg_mgcp_rtp_ip_dscp_cmd,
 	      X(MGW_CMD_ATTR_NEWCONN),
-	      "rtp ip-dscp <0-255>",
+	      "rtp ip-dscp <0-63>",
 	      RTP_STR
-	      "Apply IP_TOS to the audio stream (including Osmux)\n" "The DSCP value\n")
+	      "Use specified DSCP for the audio stream (including Osmux)\n" "The DSCP value\n")
 {
 	int dscp = atoi(argv[0]);
 	g_cfg->endp_dscp = dscp;
 	return CMD_SUCCESS;
 }
 
-ALIAS_DEPRECATED(cfg_mgcp_rtp_ip_dscp, cfg_mgcp_rtp_ip_tos_cmd,
-		 "rtp ip-tos <0-255>",
-		 RTP_STR
-		 "Apply IP_TOS to the audio stream\n" "The DSCP value\n")
 #define FORCE_PTIME_STR "Force a fixed ptime for packets sent"
 DEFUN_USRATTR(cfg_mgcp_rtp_force_ptime,
 	      cfg_mgcp_rtp_force_ptime_cmd,
@@ -1622,7 +1618,6 @@
 	install_element(MGCP_NODE, &cfg_mgcp_rtp_net_bind_ip_probing_cmd);
 	install_element(MGCP_NODE, &cfg_mgcp_rtp_no_net_bind_ip_probing_cmd);
 	install_element(MGCP_NODE, &cfg_mgcp_rtp_ip_dscp_cmd);
-	install_element(MGCP_NODE, &cfg_mgcp_rtp_ip_tos_cmd);
 	install_element(MGCP_NODE, &cfg_mgcp_rtp_force_ptime_cmd);
 	install_element(MGCP_NODE, &cfg_mgcp_no_rtp_force_ptime_cmd);
 	install_element(MGCP_NODE, &cfg_mgcp_rtp_keepalive_cmd);