ARM: dts: msm: update sdhc node bus vectors for msm8994

Add bus vectors to use with the bus scaling driver for sdhc nodes.
This will ensure that the is a minimum amount of performance guaranteed
by the driver.
Support for HS400 eMMC mode bus scaling for sdhc_1.

Change-Id: I9560740b934cc74adfc404bef683e3b125d644d9
Signed-off-by: Konstantin Dorfman <kdorfman@codeaurora.org>