perf: fix reproduciblity in older releases of Linux

If you build perf from Linux 5.4 it still contains buildpaths (pointing
to the sysroot's Python) as the existing fixes don't apply to the lines
in that old release.

Add further expressions to remove the final buildpaths.

Signed-off-by: Ross Burton <ross.burton@arm.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>