perf evsel: Introduce evsel_fprintf.h

We already had evsel_fprintf.c, add its counterpart, so that we can
reduce evsel.h a bit more.

We needed a new perf_event_attr_fprintf.c file so as to have a separate
object to link with the python binding in tools/perf/util/python-ext-sources
and not drag symbol_conf, etc into the python binding.

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-06bdmt1062d9unzgqmxwlv88@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/python-ext-sources

@@ -10,6 +10,7 @@ util/python.c
 util/cap.c
 util/evlist.c
 util/evsel.c
+util/perf_event_attr_fprintf.c
 util/cpumap.c
 util/memswap.c
 util/mmap.c