FS-7570: fix status variable reference that is breaking compile w/ zrtp enabled

src/switch_rtp.c

@@ -7746,7 +7746,7 @@ SWITCH_DECLARE(switch_status_t) switch_rtp_write_raw(switch_rtp_t *rtp_session,
 				break;
 			case zrtp_status_drop:
 				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Error: zRTP protection drop with code %d\n", stat);
-				ret = SWITCH_STATUS_SUCCESS;
+				status = SWITCH_STATUS_SUCCESS;
 				goto end;
 				break;
 			case zrtp_status_fail: