osmux: Define osmux_dummy cfg as boolean

Change-Id: Ifc3384f9871ddfdbd6282c6e03bf6a2dd8a09a9e
diff --git a/src/libosmo-mgcp/mgcp_vty.c b/src/libosmo-mgcp/mgcp_vty.c
index bc2673d..a3af94a 100644
--- a/src/libosmo-mgcp/mgcp_vty.c
+++ b/src/libosmo-mgcp/mgcp_vty.c
@@ -1639,9 +1639,9 @@
       "Disable dummy padding\n")
 {
 	if (strcmp(argv[0], "on") == 0)
-		g_cfg->osmux_dummy = 1;
+		g_cfg->osmux_dummy = true;
 	else if (strcmp(argv[0], "off") == 0)
-		g_cfg->osmux_dummy = 0;
+		g_cfg->osmux_dummy = false;
 
 	return CMD_SUCCESS;
 }