Revert "FreeSWITCH: Fix warn-unused-result error in rtp_common_read()."

*sigh* of course there are two versions of strerror_r():

	char *strerror_r() - GNU
	int strerror_r() - non-GNU

Revert and back the drawing board...

This reverts commit 3c82033e.

src/switch_rtp.c

@@ -3310,8 +3310,8 @@ static int rtp_common_read(switch_rtp_t *rtp_session, switch_payload_t *payload_
 
 			if (!SWITCH_STATUS_IS_BREAK(poll_status) && poll_status != SWITCH_STATUS_TIMEOUT) {
 				char tmp[128] = "";
-				switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_ERROR, "Poll failed with error: %d [%s]\n",
-					poll_status, strerror_r(poll_status, tmp, sizeof(tmp)));
+				strerror_r(poll_status, tmp, sizeof(tmp));
+				switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_ERROR, "Poll failed with error: %d [%s]\n", poll_status, tmp);
 				ret = -1;
 				goto end;
 			}