mmc: core: WARN if SDIO IRQs are enabled for non-powered card in suspend

To make sure SDIO func drivers behaves correctly during system
suspend/resume, let add a WARN_ON in case the condition is a non-powered
SDIO card and there are some SDIO IRQs still being claimed.
Tested-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/core/sdio.c

@@ -951,6 +951,8 @@ static int mmc_sdio_pre_suspend(struct mmc_host *host)
  */
 static int mmc_sdio_suspend(struct mmc_host *host)
 {
+	WARN_ON(host->sdio_irqs && !mmc_card_keep_power(host));
+
 	/* Prevent processing of SDIO IRQs in suspended state. */
 	mmc_card_set_suspended(host->card);
 	cancel_delayed_work_sync(&host->sdio_irq_work);