mmc: esdhc: add support to get voltage from device-tree

Add suppport to get voltage from device-tree node for esdhc host,
if voltage-ranges was specified in device-tree node we can get
ocr_mask instead of read from host capacity register. If not voltages
still can be get from host capacity register.
Signed-off-by: Haijun Zhang <haijun.zhang@freescale.com>
Acked-by: Anton Vorontsov <anton@enomsg.org>
Signed-off-by: Chris Ball <cjb@laptop.org>

drivers/mmc/host/sdhci-of-esdhc.c

@@ -316,6 +316,7 @@ static int sdhci_esdhc_probe(struct platform_device *pdev)
 
 	/* call to generic mmc_of_parse to support additional capabilities */
 	mmc_of_parse(host->mmc);
+	mmc_of_parse_voltage(np, &host->ocr_mask);
 
 	ret = sdhci_add_host(host);
 	if (ret)