swap{16,32,64} are defined as macros on the two, but client code
tries to invoke them as Common::swap{16,32,64}, which naturally
doesn't work. This hack redefines the macros as inline functions
in the Common namespace: the bodies of the functions are the
same as the original macros, but relying on OS-specific
implementation details like this is of course brittle.

This makes clang-format useful on those.

Also add a bunch of forgotten transitive includes, which otherwise
prevented compilation.

These shouldn't haphazardly convert types

This isn't well-defined in C++.

Also gets rid of pointer data variants as this prevents the use of
the regular swapping routines as unary predicates in std lib functions.

They also cast to stricter alignment types, which is undefined behavior.

Symbian, Xbox, Blackberry and iOS got removed.
FreeBSD and Android kept due to them potentially being able to run Citra in the future.
The iOS specific part also got removed from PPSSPP in order to fix a bug there.