Fix WITHOUT_NLS

Due to vim's configure not behaving like it says it does, the --disable-nls
option doesn't actually disable NLS. It linked against libintl anyway.
It turns out that to ACTUALLY disable NLS, you need to set --enable-nls to
a nonsense value.

PR: 223901
Reported by: Marian Cerny (whose name I'm butchering in 7-bit ASCII)