mmc: sdio: Check the return value of sdio_enable_4bit_bus

Since we could move card->host->caps & MMC_CAP_4_BIT_DATA
ahead of mmc_sdio_init_uhs_card, in mmc_host_uhs(). So there
we could save this bit to check that. Also, if the process of
sdio_enable_4bit_bus goes wrong, we should bails out early.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/core/sdio.c

@@ -518,11 +518,10 @@ static int mmc_sdio_init_uhs_card(struct mmc_card *card)
 	if (!card->scr.sda_spec3)
 		return 0;
 
-	/*
-	 * Switch to wider bus (if supported).
-	 */
-	if (card->host->caps & MMC_CAP_4_BIT_DATA)
-		err = sdio_enable_4bit_bus(card);
+	/* Switch to wider bus */
+	err = sdio_enable_4bit_bus(card);
+	if (err)
+		goto out;
 
 	/* Set the driver strength for the card */
 	sdio_select_driver_type(card);