freetdm: Add FTDM_COMMANDs to debug DTMF

libs/freetdm/src/include/freetdm.h

@@ -351,6 +351,7 @@ typedef struct ftdm_channel_config {
 	ftdm_chan_type_t type;
 	float rxgain;
 	float txgain;
+	uint8_t debugdtmf;
 } ftdm_channel_config_t;
 
 /*!

libs/freetdm/src/include/private/ftdm_core.h

@@ -355,6 +355,7 @@ typedef struct {
 #define DTMF_DEBUG_TIMEOUT 250
 typedef struct {
 	uint8_t enabled;
+	uint8_t requested;
 	FILE *file;
 	int32_t closetimeout;
 	ftdm_mutex_t *mutex;