Use getOriginalInit instead of PatternBindingEntry::hasInitStringRepresentation

[davidungar]

Attempt a fix for serialization (i.e. -emit-module) for source code:

@propertyWrapper
public struct TestWrapper {
  public var wrappedValue: Int
  public init(wrappedValue: Int) { self.wrappedValue = wrappedValue }
}

@frozen public struct Test {
  @TestWrapper public var x: Int = 42
}

rdar://80449046

[davidungar]

@swift-ci please test

[swift-ci]

Build failed
Swift Test Linux Platform
Git Sha - e060363

[davidungar]

@swift-ci please test

[swift-ci]

Build failed
Swift Test Linux Platform
Git Sha - fc0eca5

[davidungar]

@swift-ci please smoke test linux platform

[xymus]

Looks good, thanks!

[davidungar]

Thank you, @xymus !