const runtime.scavChunkInUseMask

2 uses

	runtime (current package)
		mgcscavenge.go#L1268: 		lastInUse:      uint16(sc>>16) & scavChunkInUseMask,
		mgcscavenge.go#L1306: 	scavChunkInUseMask   = (1 << logScavChunkInUseMax) - 1