mmc: core: mmc DDR mode should not depend on UHS_DDR50

The MMC_CAP_UHS_DDR50 must work on 1.8v.
However, the eMMC DDR mode can work on either 1.8v or 3.3v and
should not depend on UHS_DDR50.
So get rid of this limitation to let controller without 1.8v
signal voltage support can also work for eMMC DDR mode if it claims.

Signed-off-by: Dong Aisheng <[e-mail]>
Acked-by: Shawn Guo <[e-mail]>
Acked-by: Ulf Hansson <[e-mail]>
Signed-off-by: Chris Ball <[e-mail]>

drivers/mmc/core/mmc.c

···
 	 */
 	if (mmc_card_highspeed(card)) {
 		if ((card->ext_csd.card_type & EXT_CSD_CARD_TYPE_DDR_1_8V)
-			&& ((host->caps & (MMC_CAP_1_8V_DDR |
-			     MMC_CAP_UHS_DDR50))
-				== (MMC_CAP_1_8V_DDR | MMC_CAP_UHS_DDR50)))
+			&& (host->caps & MMC_CAP_1_8V_DDR))
 				ddr = MMC_1_8V_DDR_MODE;
 		else if ((card->ext_csd.card_type & EXT_CSD_CARD_TYPE_DDR_1_2V)
-			&& ((host->caps & (MMC_CAP_1_2V_DDR |
-			     MMC_CAP_UHS_DDR50))
-				== (MMC_CAP_1_2V_DDR | MMC_CAP_UHS_DDR50)))
+			&& (host->caps & MMC_CAP_1_2V_DDR))
 				ddr = MMC_1_2V_DDR_MODE;
 	}