Function attempt_log

plugins/xpay/xpay.c:271–285

	PRINTF_FMT(3,4);

static void attempt_log(struct attempt *attempt,
			enum log_level level,
			const char *fmt,
			...)
{
	va_list args;
	const char *msg, *path;

	va_start(args, fmt);
	msg = tal_vfmt(tmpctx, fmt, args);
	va_end(args);
	path = fmt_path(tmpctx, attempt);

	payment_log(attempt->payment, level, "%s: %s", path, msg);
}

#define attempt_unusual(attempt, fmt, ...) \
	attempt_log((attempt), LOG_UNUSUAL, (fmt), __VA_ARGS__)