perf, sched migration: Ignore unhandled task states

Stop printing an error message when we don't have the letter
for a given task state. All we need to know is if the task is
in the TASK_RUNNING state.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Nikhil Rao <ncrao@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>

diff --cc tools/perf/scripts/python/sched-migration.py
Simple merge