mmc: sdhci-pxav3: Respect MMC_DDR52 timing on uhs signaling

commit bb8175a8aa42d731a840cd474e348ac3367eb5a0
  ("mmc: sdhci: clarify DDR timing mode between SD-UHS and eMMC")
added MMC_DDR52 as eMMC's DDR mode to be distinguished from SD-UHS.

While the differentation may be useful, pxav3 SDHCI controller lacks
a corresponding check in its custom .set_uhs_signaling callback for
MMC_DDR52. This patch adds a new switch case for MMC_TIMING_MMC_DDR52
to MMC_TIMING_UHS_DDR50 case.

Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
diff --git a/drivers/mmc/host/sdhci-pxav3.c b/drivers/mmc/host/sdhci-pxav3.c
index 5036d7d..b55c807 100644
--- a/drivers/mmc/host/sdhci-pxav3.c
+++ b/drivers/mmc/host/sdhci-pxav3.c
@@ -211,6 +211,7 @@
 	case MMC_TIMING_UHS_SDR104:
 		ctrl_2 |= SDHCI_CTRL_UHS_SDR104 | SDHCI_CTRL_VDD_180;
 		break;
+	case MMC_TIMING_MMC_DDR52:
 	case MMC_TIMING_UHS_DDR50:
 		ctrl_2 |= SDHCI_CTRL_UHS_DDR50 | SDHCI_CTRL_VDD_180;
 		break;