x86 TLS relocation checks

Some configurations (eg. i386-bsd, i386-msdos) broke with the addition
of the TLS relocation checking.  The "x86_elf_abi undeclared" error
has been fixed, but "gotrel defined but not used" remains.  Fix that.
Also invert the preprocessor test around lex_got to make it positive
logic and remove the LEX_AT condition which is no longer necessary.
(The only x86 config files defining LEX_AT also define TE_PE.)