perf python: Remove some unused macros (_PyUnicode_FromString(arg), etc)

perf python: Remove some unused macros (_PyUnicode_FromString(arg), etc)

When python2 support was removed in e7e9943c87d857da ("perf python:
Remove python 2 scripting support"), all use of the
_PyUnicode_FromString(arg), _PyUnicode_FromFormat(...), and
_PyLong_FromLong(arg) macros was removed as well, so remove it.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20250312203141.285263-3-acme@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>