Fix: Always use 'WSLInterop` as the binfmt name

[benhillis]

This change switches the systemd unit used to prevent overriding of the WSL interop binfmt interpreter to use the original name for the interpreter. This is being done because at least one codebase (azure logon cli) has taken a dependency on the presence of this specifically named entry.

For testing I have run though the interop / binfmt unit tests, as well as verified that WSL interop continues to function even if a conflicting interpreter (such as the mono runtime) is installed.

[Copilot]

Pull Request Overview

This PR fixes an issue where WSL was using a different binfmt name (WSLInterop-late) for late registration, causing compatibility problems with external tools like Azure CLI that depend on the original WSLInterop name. The change ensures that the same name is used consistently for both initial and late binfmt registration.

Key changes:

• Removes the LX_INIT_BINFMT_NAME_LATE constant and its documentation
• Updates the systemd unit to use the original LX_INIT_BINFMT_NAME for late registration

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
src/linux/init/binfmt.h	Removes the separate late binfmt name constant and its documentation
src/linux/init/init.cpp	Updates systemd unit to use the original binfmt name instead of the late variant