[PATCH] Add support for x86_64-*-netbsd* target

[DJ Delorie]

> I looked over them as x86-64 maintainer I looked over them and they're
> fine.
> 
> But I fear that the configure part is "outside of the immediate domain
> that" I maintain (see binutils/MAINTAINERS) and I can't give a formal
> approval.  But I'll volunteer to commit this if somebody else oks it
> since you don't have CVS access AFAIK.

For gcc, a target maintainer also maintains the target-specific code
in the configury.  I see no reason to do it differently here.