[gold commit] PR 20216: Fix extraneous complaints about missing expected TLS relocation

[Cary Coutant]

> gold/
>         PR gold/20216
>         * x86_64.cc (Target_x86_64::Relocate::relocate): Add check for
>         R_X86_64_GOTPCREL. Reset skip_call_tls_get_addr_ after printing
>         error message.
>         * testsuite/Makefile.am (pr20216_gd.o): Add -Bgcctestdir/.
>         (pr20216_ld.o): Likewise.
>         * testsuite/Makefile.in: Regenerate.

I've backported this to the 2.27 branch.

-cary