There's a false positive on perf/util:
	tools/perf/util/s390-cpumsf.c: Documentation/perf.data-file-format.txt
The file is there at tools/perf/Documentation/, but the logic
with detects relative documentation references inside tools is
not capable of detecting it.
So, improve it.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
                if ($f =~ m/tools/) {
                        my $path = $f;
                        $path =~ s,(.*)/.*,$1,;
-                       next if (grep -e, glob("$path/$ref $path/$fulref"));
+                       next if (grep -e, glob("$path/$ref $path/../$ref $path/$fulref"));
                }
 
                # Discard known false-positives