tests/eas/acceptance: Add cpu_frequency to default ftrace events
tests/eas/acceptance: Add cpu_frequency to default ftrace events

This is useful for analysing traces to diagnose failures

ARM-software/lisa,mdigiorgio/lisa,credp/lisa,ARM-software/lisa,arnoldlu/lisa,ARM-software/lisa,credp/lisa,joelagnel/lisa,arnoldlu/lisa,bjackman/lisa,bjackman/lisa,credp/lisa,credp/lisa,mdigiorgio/lisa,ARM-software/lisa,joelagnel/lisa