mmc: sdhci: add delay after the last tuning command

When host set the host->tuning_delay, even the last tuning
command need a delay, otherwise the first command after the
tuning will meet issue.

Take i.MX7D as an example, there will be the following log:
  mmc2: switch to high-speed from hs200 failed, err:-110
  mmc2: error -110 whilst initialising MMC card
Signed-off-by: NHaibo Chen <haibo.chen@nxp.com>
Acked-by: NAdrian Hunter <adrian.hunter@intel.com>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/sdhci.c

@@ -2376,6 +2376,10 @@ static int __sdhci_execute_tuning(struct sdhci_host *host, u32 opcode)
 			return -ETIMEDOUT;
 		}
 
+		/* Spec does not require a delay between tuning cycles */
+		if (host->tuning_delay > 0)
+			mdelay(host->tuning_delay);
+
 		ctrl = sdhci_readw(host, SDHCI_HOST_CONTROL2);
 		if (!(ctrl & SDHCI_CTRL_EXEC_TUNING)) {
 			if (ctrl & SDHCI_CTRL_TUNED_CLK)
@@ -2383,9 +2387,6 @@ static int __sdhci_execute_tuning(struct sdhci_host *host, u32 opcode)
 			break;
 		}
 
-		/* Spec does not require a delay between tuning cycles */
-		if (host->tuning_delay > 0)
-			mdelay(host->tuning_delay);
 	}
 
 	pr_info("%s: Tuning failed, falling back to fixed sampling clock\n",