Add htonl, htons, ntohl, ntohs

[safinaskar]

Not a breaking change

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[JohnTitor]

We could split the declaration for that target.

[safinaskar]

We could split the declaration for that target

@JohnTitor , yes, we can. But I think this is slightly more error-prone than my approach. I. e. if we split the declaration, then it is possible we introduce bug for some platform, but not for others

[tgross35]

I generally agree with JohnTitor here that most things should just use the host functions if available, concerns about bugs on one platform but not others isn't much of a concern when one of those platforms uses the system functions.

However, these are also straightforward enough that it doesn't seem worth the effort to split. So I think this is okay.