Revert "freetdm: ftmod_wanpipe: Do not attempt to initialize hwdtmf in GSM ports during shutdown"

This reverts commit b29a41bb.

This commit is no longer needed now that proper infrastructure has been
added to allow signaling modules to generate and detect DTMF

The feature macros should only be used for I/O module features
and not for signaling module features

libs/freetdm/src/ftmod/ftmod_wanpipe/ftmod_wanpipe.c

@@ -1721,8 +1721,8 @@ static FIO_CHANNEL_DESTROY_FUNCTION(wanpipe_channel_destroy)
 		/* enable HW DTMF. As odd as it seems. Why enable when the channel is being destroyed and won't be used anymore?
 		 * because that way we can transfer the DTMF state back to the driver, if we're being restarted we will set again
 		 * the FEATURE_DTMF flag and use HW DTMF, if we don't enable here, then on module restart we won't see
-		 * HW DTMF available and will use software (except for GSM cards which enable hw dtmf on the signaling module) */
-		if (ftdmchan->span->trunk_type != FTDM_TRUNK_GSM && ftdm_channel_test_feature(ftdmchan, FTDM_CHANNEL_FEATURE_DTMF_DETECT)) {
+		 * HW DTMF available and will use software */
+		if (ftdm_channel_test_feature(ftdmchan, FTDM_CHANNEL_FEATURE_DTMF_DETECT)) {
 			wanpipe_tdm_api_t tdm_api;
 			int err;
 			memset(&tdm_api, 0, sizeof(tdm_api));