mmc: dw_mmc: use mmc_regulator_get_supply to handle regulators

This patch makes use of mmc_regulator_get_supply() to handle
the vmmc and vqmmc regulators.Also it moves the code handling
the these regulators to dw_mci_set_ios().It turned on the vmmc
and vqmmc during MMC_POWER_UP and MMC_POWER_ON,and turned off
during MMC_POWER_OFF.

Signed-off-by: Yuvaraj Kumar C D <yuvaraj.cd@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

include/linux/mmc/dw_mmc.h

@@ -188,7 +188,7 @@ struct dw_mci {
 	/* Workaround flags */
 	u32			quirks;
 
-	struct regulator	*vmmc;	/* Power regulator */
+	bool			vqmmc_enabled;
 	unsigned long		irq_flags; /* IRQ flags */
 	int			irq;
 };