perf script python: Remove mixed indentation

Remove mixed indentation in Python scripts.  Revert to either all tabs
(most common form) or all spaces (4 or 8) depending on what was the
intent of the original commit.  This is necessary to complete Python3
support as it will flag an error if it encounters mixed indentation.

Signed-off-by: Tony Jones <tonyj@suse.de>
Link: http://lkml.kernel.org/r/20190302011903.2416-2-tonyj@suse.de


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>