Fix Rocket decompression.

It wasn't accounting for the output size in the header, causing it to
produce garbage data after the end of the decompressed data by
processing the unused descriptor bits in the last field that it read.

src/lib/rocket.cc

@@ -127,11 +127,11 @@ struct rocket_internal {
         using RockIStream = LZSSIStream<RocketAdaptor>;
         using diff_t      = make_signed_t<size_t>;
 
-        in.ignore(2);
-        size_t const Size = BigEndian::Read2(in) + 4;
+        size_t const OutSize = BigEndian::Read2(in);
+        size_t const InSize = BigEndian::Read2(in) + 4;
         RockIStream  src(in);
 
-        while (in.good() && size_t(in.tellg()) < Size) {
+        while (in.good() && size_t(in.tellg()) < InSize && size_t(Dst.tellp()) < OutSize) {
             if (src.descbit() != 0U) {
                 // Symbolwise match.
                 uint8_t const Byte = Read1(in);