ARM: dts: msm: Support 16bit vlevel setting from SAW for 8909W

Update pvc port configuration for sending upper byte of 16bit
vlevel and remove bypass spm entry from PM660 regulator node
for 8909W + PM660.

Change-Id: Id176c4b96e2df1c8a0f36aab32d908c769e3c670
Signed-off-by: Srinivas Rao L <lsrao@codeaurora.org>