mmc: sirf: fix the capbility to support DDR50

According to hardware spec, validate DDR50 mode
for SDXC.

Signed-off-by: Weijun Yang <york.yang@csr.com>
Signed-off-by: Barry Song <Baohua.Song@csr.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/sdhci-sirf.c

@@ -50,7 +50,8 @@ static u32 sdhci_sirf_readl_le(struct sdhci_host *host, int reg)
 	if (unlikely((reg == SDHCI_CAPABILITIES_1) &&
 			(host->mmc->caps & MMC_CAP_UHS_SDR50))) {
 		/* fake CAP_1 register */
-		val = SDHCI_SUPPORT_SDR50 | SDHCI_USE_SDR50_TUNING;
+		val = SDHCI_SUPPORT_DDR50 |
+			SDHCI_SUPPORT_SDR50 | SDHCI_USE_SDR50_TUNING;
 	}
 
 	if (unlikely(reg == SDHCI_SLOT_INT_STATUS)) {