swiftc crashes on -emit-supported-features

[hnrklssn]

Description

Locally built swiftc crashes when called with -emit-supported-features.

Reproduction

No input program needed, just run:

$ build/Ninja-RelWithDebInfoAssert/swift-macosx-arm64/bin/swiftc -emit-supported-features

Stack dump

output:

SwiftDriver/Driver.swift:2311: Fatal error: unhandled output mode option -emit-supported-features
fish: Job 1, '/Volumes/UserData/Code/src-swif…' terminated by signal SIGTRAP (Trace or breakpoint trap)

### Expected behavior

An appropriate error message or list of supported features

### Environment

Swift version 6.1-dev (LLVM 71fe56bbf73af5a, Swift 7d044bd62c4672a)
Target: arm64-apple-macosx15.0

### Additional information

_No response_

[AnthonyLatsis]

@hamishknight This looks like it should be transferred to the driver repo.

[rjmansfield]

Duplicate of #74910 and resolved with #1645