Revert "Skip passing -linker-path to swiftc on Darwin."
Revert "Skip passing -linker-path to swiftc on Darwin."

This reverts commit 1cfb9d959d5cb114b084bd5ab48068a9f8b808cf.

apple/swift-lldb,apple/swift-lldb,apple/swift-lldb,apple/swift-lldb,apple/swift-lldb,apple/swift-lldb