Document std.Mutex.
Document std.Mutex.

Not sure what the build platform is for the generated documentation,
and it's worth thinking about how best to deal with this pattern. It
might be worth figuring out how to rewrite this to have a single
definition of the public API with the implementation chosen at compile
time.

zig-lang/zig,raulgrell/zig,andrewrk/zig,andrewrk/zig,raulgrell/zig,zig-lang/zig,zig-lang/zig,raulgrell/zig,raulgrell/zig,raulgrell/zig