tools lib api fs tracing_path: Make tracing_events_path private

Not anymore accessed outside this library, keep it private.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/n/tip-wg1m07flfrg1rm06jjzie8si@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/lib/api/fs/tracing_path.h

@@ -5,8 +5,6 @@
 #include <linux/types.h>
 #include <dirent.h>
 
-extern char tracing_events_path[];
-
 DIR *tracing_events__opendir(void);
 
 void tracing_path_set(const char *mountpoint);