HX DOS build breaks because of reference to _fseeki64/_ftelli64, remove duplicate dr_flac.h

[treloret]

Further split the win portion of the #define structure for fseek/ftell, and removed the duplicate dr_flac.h

What issue(s) does this PR address?

HX build doesn't work anymore since my additions yesterday.

Does this PR introduce new feature(s)?

No

Does this PR introduce any breaking change(s)?

dr_flac.h is now the latest version, according to the changelog there shouldn't be any breaking changes with the previous version

Additional information

No real means to test if it works, besides letting the HX DOS build run its flow, HX seems to be mingw, but if has mingw64 defined, this error will still occur, if that happens, then I'll have to find another way to identify that the 64-variants of fseek/ftell aren't to be used

[treloret]

Silly typo that doesn't break on a linux build, hopefully this fixes all.

[maron2000]

Is the duplicated dr_flac.h removed?
I don't see it in the Files changed tab.

[treloret]

Is the duplicated dr_flac.h removed? I don't see it in the Files changed tab.

Clearly I'm a novice with git, because somehow those changes were reverted, I'll see that it gets in.

[treloret]

I tried to keep the changes to libchdr to a minimum, besides the assembly removal and some void* casts, and the breaking fseek/ftell macros, so that any future changes to libchdr should be easier, that includes the reversal of some removed lzmaenc.c functions. Was glorious to see Bleifuss starting up and playable. Zstd deprecated/legacy could probably be removed, and I believe I'm breaking some FOSS code by not including the license files for lzma/zstd, should probably add that.