Allocate per-payload-type stats buffers in shared bufferpool. Push these
to the kernel module for direct tracking of bytes/packets stats. This
eliminates the need to return these values in the /blist data and
continuously update the userspace stats.
The accomodate updating the payload-type tracker, we use the "last
received" timestamp from the kernel module together with the "last seen
payload type" to give similar results as before.
Change-Id: I524791a1940b5d1ff2d82716c3b7a262f64e106c