ARM: dts: Keep eMMC regulators soft-disabled for exynos4412-trats2

In MAX77686 PMIC two regulators dedicated for eMMC memory can be
controlled both by I2C interface and a GPIO pin, with the resulting
regulator state being a logical OR of both. Since the GPIO control is
used both by the kernel and the lowest level bootloader at reset, the
regulator should be disabled by I2C control to allow it to be turned off
by GPIO control.

This patch removes regulator-always-on properties from both regulators
and, while at it, also unsupported regulator-mem-off.

Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>