freetdm: make array len macro public

libs/freetdm/src/include/ftdm_os.h

@@ -67,6 +67,9 @@ extern "C" {
 /*! \brief check for zero length string buffer */
 #define ftdm_strlen_zero_buf(s) (*s == '\0')
 
+/*! \brief array len helper */
+#define ftdm_array_len(array) sizeof(array)/sizeof(array[0])
+
 /*! \brief The memory handler. 
     Do not use directly this variable, use the memory macros and ftdm_global_set_memory_handler to override */	
 FT_DECLARE_DATA extern ftdm_memory_handler_t g_ftdm_mem_handler;

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

@@ -589,8 +589,6 @@ FT_DECLARE(ftdm_status_t) ftdm_channel_queue_dtmf(ftdm_channel_t *ftdmchan, cons
 */
 #define ftdm_socket_close(it) if (it > -1) { close(it); it = -1;}
 
-#define ftdm_array_len(array) sizeof(array)/sizeof(array[0])
-
 #define ftdm_channel_lock(chan) ftdm_mutex_lock(chan->mutex)
 #define ftdm_channel_unlock(chan) ftdm_mutex_unlock(chan->mutex)
 #define ftdm_log_chan_ex(fchan, file, func, line, level, format, ...) ftdm_log(file, func, line, level, "[s%dc%d][%d:%d] " format, fchan->span_id, fchan->chan_id, fchan->physical_span_id, fchan->physical_chan_id, __VA_ARGS__)