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

libraries/libstratosphere/include/stratosphere/fs/fs_rights_id.hpp

@@ -23,7 +23,7 @@ namespace ams::fs {
         u64 data64[2];
     };
     static_assert(sizeof(RightsId) == 0x10);
-    static_assert(std::is_pod<RightsId>::value);
+    static_assert(util::is_pod<RightsId>::value);
 
     inline bool operator==(const RightsId &lhs, const RightsId &rhs) {
         return std::memcmp(std::addressof(lhs), std::addressof(rhs), sizeof(RightsId)) == 0;