In preparation for an ARM simulator framework update create_ios_framework to replace --simulator-out-dir with --simulator-x86-out-dir and --simulator-arm64-out-dir. lipo the simulator frameworks together.

When that's done, update the recipe logic that calls this script to pass in --simulator-x86-out-dir.
When #64502 is ready, it will additionally pass in --simulator-arm64-out-dir.

Don't remove deprecated --simulator-out-dir until after the recipe is updated to avoid breaking changes.