lpm-levels: Wakeup the isolated core for new PMQoS update

Wakeup the isolated core for every new PMQoS update so that
we can re-evaluate the core lpm with new updated PMQoS latency
request.

Change-Id: I969ad216ab353f2dbfe4fc54a75000fa0140fce9
Signed-off-by: Raghavendra Kakarla <rkakarla@codeaurora.org>