scripts: strip leading './' when searching MAINTAINERS file

The following two uses of get_maintainer.pl should return the
same results, but do not:

  $ ./scripts/get_maintainer.pl -f ./hw/net/vmxnet3.c
  get_maintainer.pl: No maintainers found, printing recent contributors.
  get_maintainer.pl: Do not blindly cc: them on patches!  Use common sense.

  "Philippe Mathieu-Daudé" <philmd@linaro.org> (commit_signer:4/7=57%)
  "Michael S. Tsirkin" <mst@redhat.com> (commit_signer:4/7=57%)
  Xiaoyao Li <xiaoyao.li@intel.com> (commit_signer:3/7=43%)
  Thomas Huth <thuth@redhat.com> (commit_signer:3/7=43%)
  Zhao Liu <zhao1.liu@intel.com> (commit_signer:3/7=43%)
  qemu-devel@nongnu.org (open list:All patches CC here)

  $ ./scripts/get_maintainer.pl -f hw/net/vmxnet3.c
  Dmitry Fleytman <dmitry.fleytman@gmail.com> (maintainer:VMware)
  Jason Wang <jasowang@redhat.com> (odd fixer:Network devices)
  qemu-devel@nongnu.org (open list:All patches CC here)

In the former case, the leading "./" needs to be removed before
trying to find a filename match.

Blindly stripping the "./" is valid because the script already
enforces that it is run from the QEMU git root directory, so
canonicalizing the filename vs $CWD is not required.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-ID: <20260511093858.82753-1-berrange@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>

scripts/get_maintainer.pl

@@ -384,6 +384,7 @@ foreach my $file (@ARGV) {
 	} elsif (!(stat $file)) {
 	    die "$P: file '${file}' not found: $!\n";
 	}
+	$file =~ s,^./,,;
     }
     if ($from_filename) {
 	push(@files, $file);