libs/utils/trace_analysis: add title support for cluster frequencies plot
libs/utils/trace_analysis: add title support for cluster frequencies plot

Signed-off-by: Patrick Bellasi <431c86f368affbc3148c4669fbd465131f7e82cb@arm.com>

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