spandsp windows build fix

libs/spandsp/src/fax_modems.c

@@ -98,7 +98,7 @@ static void fax_modems_hdlc_accept(void *user_data, const uint8_t *msg, int len,
 }
 /*- End of function --------------------------------------------------------*/
 
-SPAN_DECLARE(void) fax_modems_hdlc_tx_frame(void *user_data, const uint8_t *msg, int len)
+SPAN_DECLARE_NONSTD(void) fax_modems_hdlc_tx_frame(void *user_data, const uint8_t *msg, int len)
 {
     fax_modems_state_t *s;
 

libs/spandsp/src/spandsp/fax_modems.h

@@ -65,7 +65,7 @@ SPAN_DECLARE_NONSTD(int) fax_modems_v17_v21_rx_fillin(void *user_data, int len);
 SPAN_DECLARE_NONSTD(int) fax_modems_v27ter_v21_rx_fillin(void *user_data, int len);
 SPAN_DECLARE_NONSTD(int) fax_modems_v29_v21_rx_fillin(void *user_data, int len);
 
-SPAN_DECLARE(void) fax_modems_hdlc_tx_frame(void *user_data, const uint8_t *msg, int len);
+SPAN_DECLARE_NONSTD(void) fax_modems_hdlc_tx_frame(void *user_data, const uint8_t *msg, int len);
 
 SPAN_DECLARE(void) fax_modems_hdlc_tx_flags(fax_modems_state_t *s, int flags);