hos: allow turning off ams extension hard-reqs for unit testing

libstrat: remove lingering debugging edits

ams: replace most remaining operator & with std::addressof

strat: use ams::Main() instead of main(argc, argv)

libstrat: enable -Wextra, -Werror ...

This caught an embarrassingly large number of bugs.

ams-libs: fix change detection for library building

sm: update to excise unnecessary library code

sm: reimplement using tipc instead of cmif (probably broken, untested)

tipc: fix compilation issues with core serialization routines

libstrat: move weak HasLaunchedBootProgram to non-lto object file

ro: reduce memory usage by excising (unused) std::malloc

libstrat: convert to experimental new (super-accurate) sf allocation semantics

libstrat: fix precompiled-header dependency detection

Meso build targets (#1196) ...

* meso: commit wip (thanks fincs) rewrite to support build targets

* meso: commit mostly-working build system

* meso: correct .o dependencies in kernel/kldr

* libstratosphere: fix building after PCH related build changes

Co-authored-by: fincs <fincs@devkitpro.org>

libstrat: fix building of source/os/*

ams: update build system to add generic-fallback support

libstrat: fix bugs/compiler warnings

libstrat: fix dependencies for pre-compiled header

Switch atmosphere's build target to C++20. (#952) ...

* ams: update to build with gcc10/c++20

* remove mno-outline-atomics

* ams: take care of most TODO C++20s

* fusee/sept: update for gcc10

* whoosh, your code now uses pre-compiled headers

* make: dependency fixes

mem: implement most of StandardAllocator (#860) ...

This was tested using `https://github.com/node-dot-cpp/alloc-test` plus a few other by-hand tests.

It seems to work for the case we care about (sysmodules without thread cache-ing).

External users are advised to build with assertions on and contact SciresM if you find issues.

This is a lot of code to have gotten right in one go, and it was written mostly after midnight while sick, so there are probably un-noticed issues.

crypto: Implement BigNum/ExpMod

Replace HFILES with HFILES_BIN in all makefiles

git subrepo clone https://github.com/Atmosphere-NX/Atmosphere-libs libraries ...

subrepo:
  subdir:   "libraries"
  merged:   "07af583b"
upstream:
  origin:   "https://github.com/Atmosphere-NX/Atmosphere-libs"
  branch:   "master"
  commit:   "07af583b"
git-subrepo:
  version:  "0.4.0"
  origin:   "https://github.com/ingydotnet/git-subrepo"
  commit:   "5d6aba9"