[mkgmap-dev] Commit r4513: fix obvious typo in evaluation of seamark:light:character found by sonarlint

Version mkgmap-r4513 was committed by gerd on Thu, 04 Jun 2020 fix obvious typo in evaluation of seamark:light:character found by sonarlint http://www.mkgmap.org.uk/websvn/revision.php?repname=mkgmap&rev=4513