ARM: dts: msm: Add llcc cache dump support for sm6150

sm6150 supports a single instance Last level cache controller
with 256KB system cache. Add dump size to allocate buffers
for llcc cache dumps.

Change-Id: I86adc793df960667f623a5e8853e5b2b824b9ec3
Signed-off-by: Srinivas Ramana <sramana@codeaurora.org>