[PATCH][gold] Mips: Add support for MIPS R6.

[Vladimir Radosavljevic]

> (Several places) More info would be useful in these error messages:
> object file, section name, offset.

Those information will be produced by code at the end of the
Target_mips::Relocate::relocate method (case for STATUS_BAD_RELOC).

> Did you have updated versions of the other two patches to send me, or
> should I just apply the originals with my suggested changes?

I have sent updated versions of these two patches.
https://sourceware.org/ml/binutils/2016-05/msg00358.html
https://sourceware.org/ml/binutils/2016-05/msg00359.html

Regards,
Vladimir