perf header: Use skip_spaces() in __write_cpudesc()

No change in behaviour.

Cc: Stephane Eranian <eranian@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-0dbfpi70aa66s6mtd8z6p391@git.kernel.org


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>