Fix a build issue affecting nim-eth/rlpx.nim

[zah]

[arnetheduck]

I have no idea what this does - but it looks like the kind of issue that would be valuable to start building up a test base around - even to serve as example of intended behavior

[arnetheduck]

@zah is this still relevant?

[zah]

This is a good change in general, but not strictly needed right now. @cheatfate asked me once about a strange build problem he was seeing and this fix was addressing it.

[arnetheduck]

so rebase and merge? ie if it's at least harmless and sometimes helps?

[arnetheduck]

closing this since it's stale and conflicts with other PR:s - we can revisit if it becomes relevant again