remove unused data from dc6 headers

formats/dc6/dc6.go

@@ -7,17 +7,11 @@ import (
 	"github.com/FooSoft/lazarus/streaming"
 )
 
-const (
-	FlagIsSerialized = 1 << iota
-	FlagIsLoadedInHw
-	FlagIs24Bits
-)
-
 type fileHeader struct {
 	Version         uint32
-	Flags        uint32
-	Format       uint32
-	SkipColor    uint32
+	UnusedFlags     uint32
+	UnusedFormat    uint32
+	UnusedSkipColor uint32
 	DirCount        uint32
 	FramesPerDir    uint32
 }
@@ -28,8 +22,8 @@ type frameHeader struct {
 	Height          uint32
 	OffsetX         uint32
 	OffsetY         uint32
-	AllocSize uint32
-	NextBlock uint32
+	UnusedAllocSize uint32
+	UnusedNextBlock uint32
 	Length          uint32
 }