fix warnings

src/switch_channel.c

@@ -446,7 +446,7 @@ SWITCH_DECLARE(switch_status_t) switch_channel_queue_dtmf_string(switch_channel_
 		dur = switch_core_default_dtmf_duration(0) / 8;
 		if ((p = strchr(argv[i], '@'))) {
 			*p++ = '\0';
-			if ((dur = atoi(p)) > switch_core_min_dtmf_duration(0) / 8) {
+			if ((dur = atoi(p)) > (int)switch_core_min_dtmf_duration(0) / 8) {
 				dtmf.duration = dur * 8;
 			}
 		}

src/switch_ivr_async.c

@@ -2364,7 +2364,7 @@ static switch_bool_t inband_dtmf_generate_callback(switch_media_bug_t *bug, void
 						int duration = dtmf->duration;
 
 						buf[0] = dtmf->digit;
-						if (duration > switch_core_max_dtmf_duration(0)) {
+						if (duration > (int)switch_core_max_dtmf_duration(0)) {
 							duration = switch_core_default_dtmf_duration(0);
 							switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(switch_core_media_bug_get_session(bug)),
 										  SWITCH_LOG_WARNING, "%s Truncating DTMF duration %d ms to %d ms\n",