Get latest smmalloc

We have an old version of the lib which leaks some `INLINE` macro that conflicts with other libraries and necessitates a dedicated wrapper header:
https://github.com/beyond-all-reason/RecoilEngine/blob/d6e9943238dc50dc7e4ebab8694ea66ac4c55835/rts/System/recoil-smmalloc.h#L5

Latest smmalloc has this fixed: https://github.com/SergeyMakeev/smmalloc/blob/master/SmMalloc/smmalloc.h#L120

See if we can update that dependency to latest.

Start with rts/System/recoil-smmalloc.h and compare its wrapper need with the latest smmalloc.h at the linked upstream location. Locate the dependency definition in the repository, update it to the latest smmalloc version, and verify that the wrapper is no longer needed while the project still builds.

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