mmc: dw_mmc: set to MMC_CAP_ERASE by default

This flag needs to use the trim/discard/erase commands.
dwmmc controller enables this flag by default.

Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/dw_mmc.c

@@ -2604,6 +2604,12 @@ static int dw_mci_init_slot(struct dw_mci *host, unsigned int id)
 	if (host->pdata->caps)
 		mmc->caps = host->pdata->caps;
 
+	/*
+	 * Support MMC_CAP_ERASE by default.
+	 * It needs to use trim/discard/erase commands.
+	 */
+	mmc->caps |= MMC_CAP_ERASE;
+
 	if (host->pdata->pm_caps)
 		mmc->pm_caps = host->pdata->pm_caps;