[macCatalyst] Add some build presets for CI testing

[drodriguez]

None of the presets exercise macCatalyst at the moment. The presets provided in this commit are not used by default, and will need to be invoked specially with the Swift CI bot, but at least it will allow testing the macCatalyst features.

[drodriguez]

preset=buildbot_incremental,tools=RA,stdlib=RA,test=macCatalyst,type=device
@swift-ci please test with preset macOS platform

[drodriguez]

Failed Tests (4):
  Swift(macosx-x86_64) :: ClangImporter/availability_maccatalyst.swift
  Swift(macosx-x86_64) :: ClangImporter/availability_maccatalyst_app_extension.swift
  Swift(macosx-x86_64) :: IRGen/temporary_allocation/codegen_very_large_allocation.swift
  Swift(macosx-x86_64) :: Misc/maccatalyst_load_commands.swift

For ClangImporter/availability_maccatalyst.swift and ClangImporter/availability_maccatalyst_app_extension.swift needs to modify https://github.com/swiftlang/swift/blob/main/lib/ClangImporter/ClangImporter.cpp#L2648-L2651 and outside treatDeprecatedAsUnavailable to avoid implicit availability for macCatalyst overriding the iOS availability attribute. availableOnIOSButUnavailableOnmacCatalyst and others don't exist and unavailableOnIOS is incorrectly named.

[drodriguez]

@swift-ci please test

[drodriguez]

@shahmishal : can you check if this follows the right naming? It is not clear to me if Apple has some presets internally for macCatalyst or if these ones will interfere. It is useful in PRs like #77506 to show that the current open source tests are not passing for macCatalyst.