ARM: dts: msm: remove LLCC bwmon node for sdm670.

CPUSS address space will not be cacheable in LLCC for
sdm670, the traffic seen at memnoc will land up in DDR
for sdm670 will have only one bwmon node to monitor traffic
and vote DDR, so remove LLCC bwmon node from sdm670.

Change-Id: I4760a87cbcb9317b3f7a4380b42c55c367d7536b
Signed-off-by: Santosh Mardi <gsantosh@codeaurora.org>