Update LightMessaging.h

[mostm]

What does this implement/fix? Explain your changes.

Unable to compile without change. I'm not sure if this qualifies under code rules, feel free to edit the change.

Checklist

• [ ] New code follows the code rules
• [ ] I've added modulemaps for any new libraries (e.g. see libactivator/module.modulemap): it should be possible to @import MyLibrary; in ObjC, or import MyLibrary in Swift.
• [x] My contribution is code written by myself from reverse-engineered headers, licensed into the Public Domain as per LICENSE.md; or, code written by myself / taken from an existing project, released under an OSI-approved license, and I've added relevant licensing credit to LICENSE.md

Does this close any currently open issues?

…

Any relevant logs, error output, etc?

make do output from one of the tweaks: https://gist.github.com/mostm/66adb7980477cfdfbc03b65a597991a1

Where has this been tested?

Operating System: macOS Big Sur

Platform: macOS

Target Platform: iOS 14.5

Toolchain Version: Xcode 12.5.1

SDK Version: 14.5