Scan: Avoid Perl warning on fonts with missing /Version

scan/scan

@@ -356,7 +356,7 @@ AMEN
 		$fname =~ s/[()]//g;
 		my $ename = $standard_encodings{$ehash} // "Special";
 		print "# encoding hash: $ehash\n" if $verbose;
-		print "*Font $fname: ", $ename, " \"", $g->{'/Version'}, "\" ", $ename, " ROM\n";
+		print "*Font $fname: ", $ename, " \"", ($g->{'/Version'} // '<unknown version>'), "\" ", $ename, " ROM\n";
 	}
 }