mmc: rtsx: add delay before power on

To make sure voltage is below 0.5V before power on during a power cycle,
add a delay of at least 100ms. The delays in the mmc core is not sufficient
for the rtsx pci device.
Signed-off-by: Ricky Wu <ricky_wu@realtek.com>
Link: https://lore.kernel.org/r/20210113105723.7916-1-ricky_wu@realtek.comSigned-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/rtsx_pci_sdmmc.c

@@ -906,6 +906,8 @@ static int sd_power_on(struct realtek_pci_sdmmc *host)
 	if (host->power_state == SDMMC_POWER_ON)
 		return 0;
 
+	msleep(100);
+
 	rtsx_pci_init_cmd(pcr);
 	rtsx_pci_add_cmd(pcr, WRITE_REG_CMD, CARD_SELECT, 0x07, SD_MOD_SEL);
 	rtsx_pci_add_cmd(pcr, WRITE_REG_CMD, CARD_SHARE_MODE,