ARM: dts: update ufs slave bus voting IB for SDM845

During UFS read/write test, the CNOC clock stays at 19.2MHz even through
data traffic is heavy. As the CNOC clock is low, the random read/write
performance of UFS is limited, which is much worse than data collected
on MSM8998. During heavy data traffic, the CNOC clock is expected to
scale up to 75MHz and this is what MSM8998 performs during the same
read/write test. This change updates the bus voting instanenous bandwidth
(IB) value for UFS slave in order to scale up CNOC clock to 75MHz when
UFS is working in HS G3 Rate-B 2-lane mode.

Change-Id: Id88f22780ae4893acee9e7adbb38427572bdf7f5
Signed-off-by: Can Guo <cang@codeaurora.org>