core_ctl: Consider high irq loaded CPU as busy

Currently a CPU is considered as busy if it's utilization in
the last window exceeds busy threshold. A CPU loaded with
hardirqs/softirqs does not necessarily have high utilization.
Isolating such CPUs may hurt performance as it involves waking
up the CPU frequently from deep c-state. Prevent isolating
high irq loaded CPUs by considering them as busy.

Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
[markivx: Fix trace event merge conflicts]
Signed-off-by: Vikram Mulukutla <markivx@codeaurora.org>

Change-Id: If738f90e5a36cade4046890d0d81482794e7ddea
Signed-off-by: Satya Durga Srinivasu Prabhala <satyap@codeaurora.org>