revert nim.cfg to version before b26e6e3 (#5306)
revert nim.cfg to version before b26e6e3 (#5306)

... to enable building of koch on Linux again
tulayang/Nim,russpowers/Nim,dom96/Nim,dom96/Nim,russpowers/Nim,tulayang/Nim,russpowers/Nim,dom96/Nim,russpowers/Nim,tulayang/Nim,tulayang/Nim,tulayang/Nim,russpowers/Nim,dom96/Nim,russpowers/Nim,russpowers/Nim,dom96/Nim,dom96/Nim,tulayang/Nim,dom96/Nim