Use 64-bit integer as range encoder's cache size. This fixes a

theoretical data corruption, which should be very hard to trigger
even intentionally.

src/liblzma/rangecoder/range_encoder.h

@@ -26,8 +26,8 @@
 
 typedef struct {
 	uint64_t low;
+	uint64_t cache_size;
 	uint32_t range;
-	uint32_t cache_size;
 	uint8_t cache;
 } lzma_range_encoder;