[Bug target/121998] --disable-multilib doesn't work if provision for multilib has been made.

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121998

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Plus this will break x86_64 target if you supply --disable-multilib as you
don't want the 32bit multilib but the libraries are all in lib64.