C++ interop is now enabled in SwiftCompilerSources, so we can remove some of the C bridging layer and use C++ classes directly from Swift.
rdar://83361087
To use _RegexParser from SwiftSyntax.
* Create 'libswiftCompilerModules_SwiftSyntax.a' which is a subset of
'libswiftCompilerModules.a'
* Link 'lib_InternalSwiftSyntaxParser' to
'libswiftCompilerModules_SwiftSyntax.a'
* Factor out swift runtime linking logic in CMake so that dynamic
libraries can link to Swift runtime, in addition to executables
* Link 'lib_InternalSwiftSyntaxParser' to swift runtime
This fixes:
* An issue where the diagnostic messages were leaked
* Diagnose at correct position inside the regex literal
To do this:
* Introduce 'Parse' SwiftCompiler module that is a bridging layer
between '_CompilerRegexParser' and C++ libParse
* Move libswiftParseRegexLiteral and libswiftLexRegexLiteral to 'Parse'
Also this change makes 'SwiftCompilerSources/Package.swift' be configured
by CMake so it can actually be built with 'swift-build'.
rdar://92187284
