core_ctl: Keep all CPUs un-isolated while boost is active

Currently BIG cluster CPUs are kept active while boost is enabled.
If core_ctl is used for the little cluster, these CPUs can be
isolated. Keeping all CPUs active during boost is desired for the
best performance.

Change-Id: Ife097b0b60261ea7740c8e310ae1246a3ee18826
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>
Signed-off-by: Satya Durga Srinivasu Prabhala <satyap@codeaurora.org>