[llvm][TextAPI/MachO] Support writing single macCatalyst platform

[JDevlieghere]

Summary

TAPI currently lacks a way to emit the macCatalyst platform. For TBD_V3 is does support zippered frameworks given that both macOS and macCatalyst are part of the PlatformSet.

[merge_guards_bot]

Unit tests: fail. 62150 tests passed, 5 failed and 811 were skipped.

failed: libc++.std/language_support/cmp/cmp_partialord/partialord.pass.cpp
failed: libc++.std/language_support/cmp/cmp_strongeq/cmp.strongeq.pass.cpp
failed: libc++.std/language_support/cmp/cmp_strongord/strongord.pass.cpp
failed: libc++.std/language_support/cmp/cmp_weakeq/cmp.weakeq.pass.cpp
failed: libc++.std/language_support/cmp/cmp_weakord/weakord.pass.cpp

clang-tidy: pass.

clang-format: pass.

Build artifacts: diff.json, clang-tidy.txt, clang-format.patch, CMakeCache.txt, console-log.txt, test-results.xml

Pre-merge checks is in beta. Report issue. Please join beta or enable it for your project.

[cishida]

LGTM, thank you!

llvm/lib/TextAPI/MachO/TextStubCommon.cpp

case PlatformKind::watchOS:
     OS << "watchos";
     break;
   case PlatformKind::tvOS:
     OS << "tvos";
     break;
   case PlatformKind::bridgeOS:
     OS << "bridgeos";
     break;
+  case PlatformKind::macCatalyst:
+    OS << "iosmac";
+    break;
   }
 }
 
 StringRef ScalarTraits<PlatformSet>::input(StringRef Scalar, void *IO,
                                            PlatformSet &Values) {
   const auto *Ctx = reinterpret_cast<TextAPIContext *>(IO);
   assert((!Ctx || Ctx->FileKind != FileType::Invalid) &&
          "File type is not set in context");