perf: periodic: add cpumask processing

Cpumask is used to limit the processors being profiled
on a multi-core processor. Cpumask was being set but not
being used. Add support to use cpumask when creating
a counter.

Change-Id: I3a3aab581e9e925507da5d319328ed6a2460328f
Signed-off-by: Neil Leeder <nleeder@codeaurora.org>