perf hists browser: Fix typo in function switch_data_file

Should clear buf 'abs_path', not 'options'.

Signed-off-by: Changbin Du <changbin.du@intel.com>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: 341487a ("perf hists browser: Add option for runtime switching perf data file")
Link: http://lkml.kernel.org/r/20170313114652.9207-1-changbin.du@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/ui/browsers/hists.c

@@ -2308,7 +2308,7 @@ static int switch_data_file(void)
 		return ret;
 
 	memset(options, 0, sizeof(options));
-	memset(options, 0, sizeof(abs_path));
+	memset(abs_path, 0, sizeof(abs_path));
 
 	while ((dent = readdir(pwd_dir))) {
 		char path[PATH_MAX];