Support no GPCs ("0" counters) available scenario

[PrzemekWirkus]

Cloned from: https://linaro.atlassian.net/browse/WPERF-674

This is placeholder ticket to record that WindowsPerf should properly handle edge cases for GPC availability.

For example, if WindowsPerf can acquire zero (0) GPCs we should correctly inform user space.

Other scenarios include:

• When we acquire n GPCs but we e.g. want to count event group with >n events.
  • Example: We can acquire 2 GPCs and user specifies (Telemetry Solution) metric branch_percentage which requires 3 GPC to store all events for it. See:
    • branch_percentage specifies {br_immed_spec,br_indirect_spec,inst_spec} event group,
    • metric calculates: (((br_immed_spec + br_indirect_spec) / inst_spec) * 100).

This ticket may require further break-down to smaller tickets: to test edge cases like 0 GPCs available, less events available than number of events in user-specified group(s) etc.

Note: GPC - general purpose (PMU) counter - this implies GPC is not fixed counter (cycles only).