dt-bindings: msm: update documentation of qcom,llcc

Add cap-based-alloc-and-pwr-collapse to llcc documentation. This is
to express that HLOS can enable/disable capacity based allocation
and power collapse retention for a client.

Change-Id: Ib11a2d587d18a9355cac32b01a35bcfa7ca097c3
Signed-off-by: Venkata Narendra Kumar Gutta <vnkgutta@codeaurora.org>