plugins: cache wall clk timestamp only when data is available
When querying mmap position for the first time after detection,
there may be no data ready in ADSP side, causing old wall clk
timestamp cached. This may cause unexpected behavior when we
query mmap position next time as the wall clk difference may
be very big and finally it may cause crash for lab reading in
pal side.
Cache wall clk timestamp only when frame counter changes after
query.
Change-Id: I068ae58ad73908815e29d686cbf4dc79c4001cee
1 file changed