* sysdeps/generic/errno.c (__libc_errno): Remove alias.
* inet/herrno.c (__libc_h_errno): Likewise.
* resolv/res_libc.c (__libc_res): Likewise.
[USE___THREAD]: Use this in place of [USE_TLS && HAVE___THREAD].
(__res_state) [! USE___THREAD]: Don't define as weak.
* csu/Versions: Revert last change.
* resolv/Versions: Revert last change.