test/power: add turbo mode to frequency check

test/power: add turbo mode to frequency check

With the intel_pstate driver and turbo enabled, the top frequency in
the frequency array is the P1+1, i.e. 2300001, whereas the frequency
shown in scaling_cur_freq could be a lot higher.

This patch adds a flag to the check_cur_freq function so that we can
specify if a frequency is greater than expected (turbo mode), in which
case the check should be successful.

Fixes: aeaeaf5f2d62 ("test/power: add cases for turbo feature")
Cc: stable@dpdk.org
Signed-off-by: David Hunt <david.hunt@intel.com>