Remove no longer used map checksum computation

lib/mapping/CMap.cpp

@@ -178,7 +178,6 @@ EDiggingStatus TerrainTile::getDiggingStatus(const bool excludeTop) const
 
 CMap::CMap(IGameCallback * cb)
 	: GameCallbackHolder(cb)
-	, checksum(0)
 	, grailPos(-1, -1, -1)
 	, grailRadius(0)
 	, waterMap(false)

lib/mapping/CMap.h

@@ -137,7 +137,6 @@ public:
 
 	void reindexObjects();
 
-	ui32 checksum;
 	std::vector<Rumor> rumors;
 	std::vector<DisposedHero> disposedHeroes;
 	std::vector<ConstTransitivePtr<CGHeroInstance> > predefinedHeroes;

lib/mapping/MapFormatH3M.cpp

@@ -92,19 +92,6 @@ std::unique_ptr<CMapHeader> CMapLoaderH3M::loadMapHeader()
 
 void CMapLoaderH3M::init()
 {
-	//TODO: get rid of double input process
-	si64 temp_size = inputStream->getSize();
-	inputStream->seek(0);
-
-	auto * temp_buffer = new ui8[temp_size];
-	inputStream->read(temp_buffer, temp_size);
-
-	// Compute checksum
-	boost::crc_32_type result;
-	result.process_bytes(temp_buffer, temp_size);
-	map->checksum = result.checksum();
-
-	delete[] temp_buffer;
 	inputStream->seek(0);
 
 	readHeader();