perf/core: Do not pass header for sample ID init

The only thing it does for header in __perf_event_header__init_id() is
to update the header size with event->id_header_size.  We can do this
outside and get rid of the argument for the later change.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230118060559.615653-7-namhyung@kernel.org