perf tool_pmu: Remove duplicate io.h header

Remove duplicate inclusion of api/io.h.

Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202410131417.ynhvnEJb-lkp@intel.com/


Signed-off-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20241016160413.51587-1-irogers@google.com


Signed-off-by: Namhyung Kim <namhyung@kernel.org>