msm: msm_bus: Add num aggports property

The adhoc bus scaling driver uses the number of qos ports
to determine if the path is interleaved or not.  On some
targets there are interleaved paths that don't have multiple
qos ports.  This will cause the aggregation to be incorrect.
This patch adds support for these types of paths.

Change-Id: Ib86d4313bc444b879561472a2f266c3e7be2fb10
Signed-off-by: Dan Sneddon <dsneddon@codeaurora.org>