Refactor surrounding MxDSChunk utility functions

[disinvite]

Specifically: the functions IntoType and IntoLength from the MxDSChunk header. They seek a pointer into the right place when reading the chunk, but the beta shows they are not used. The Size and End functions are used, but they are different from what we had.

These two functions are users of the utility functions:

• MxDiskStreamProvider::FUN_100d1b20 now 100%
• ReadData (from MxRAMStreamProvider) still 100% but with entropy

I'm not sure why, but this has also caused us to jump from 141 to 432 functions aligned. It may just be chance, but these two runs of functions now line up:

0001:0000b110          0  fun  103     MxEntity::~MxEntity
to
0001:00012c40          0  fun  458     LegoJetski::HitActor

and

0001:00016650          0  fun  390     CarRace::HandleClick
to
0001:00016da0          0  fun  215     PizzeriaState::Serialize

[foxtacles]

I'm not sure why, but this has also caused us to jump from 141 to 432 functions aligned. It may just be chance, but these two runs of functions now line up:

0001:0000b110          0  fun  103     MxEntity::~MxEntity
to
0001:00012c40          0  fun  458     LegoJetski::HitActor

and

0001:00016650          0  fun  390     CarRace::HandleClick
to
0001:00016da0          0  fun  215     PizzeriaState::Serialize

Probably entropy, but looks good!