High speed I2C is used on Exynos5 based SoCs. Enable it.

The MMC partition for Root filesystem cannot be mounted
without this enabling HS-I2C and regulators on many boards
are connected HS-I2C bus so the regulators don't come by
default without this.

Actually, we are not able to get arndale-octa board to boot
and mount an MMC partition without this change.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Tested-by: Javi Merino <javi.merino@arm.com>
[kgene.kim@samsung.com: modified description]
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>