It appears for Swift there was confusing errors when trying to parse APINotes, when libAPINotes and libInterfaceStub are linked, they both export symbol
`__ZN4llvm4yaml7yamlizeINS_12VersionTupleEEENSt3__19enable_ifIXsr16has_ScalarTraitsIT_EE5valueEvE4typeERNS0_2IOERS5_bRNS0_12EmptyContextE`, and discovered
same symbol defined within llvm-ifs.
This consolidates the boilerplate into YAMLTraits and defers the specific validation in reading the whole input.
fixes: rdar://problem/70450563
Reviewed By: phosek, dblaikie
Differential Revision: https://reviews.llvm.org/D89764
This change moves elfabi related code to llvm/InterfaceStub library
so it can be shared by multiple llvm tools without causing cyclic
dependencies.
Differential Revision: https://reviews.llvm.org/D85678