perf/scripts: Remove unnecessary PyTuple resizes

If we know the size of a tuple in advance, there's no need to resize
it - start out with the known size in the first place.

Signed-off-by: Tom Zanussi <tzanussi@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Keiichi KII <k-keiichi@bx.jp.nec.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1266822779.6426.4.camel@tropicana>
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>