ARM: dts: msm: Update bus bandwidth votes for sdhci on 8084

APQ8084 supports eMMC HS400 mode providing maximum throughput of
400MB/s. Update the list of bus bandwidth votes to make sure
appropriate vote is placed in this mode.

Change-Id: Iec99d608d02074d2e99f6190457dc6c1c4002c82
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>