[binutils-gdb] Fix two NetBSD-specific typos in the configure.nat conversion.

[sergiodj+buildbot@sergiodj.net]

*** TEST RESULTS FOR COMMIT b9c0e1b40ee4e7eeb3e2850720bf30f28e2e17b1 ***

Author: John Baldwin <jhb@FreeBSD.org>
Branch: master
Commit: b9c0e1b40ee4e7eeb3e2850720bf30f28e2e17b1

Fix two NetBSD-specific typos in the configure.nat conversion.

- Add the '-lkvm' library requirement for NetBSD/sparc64.
- Fix spelling of 'nbsdelf' host.

gdb/Changelog:

	* configure.nat: Add "-lkvm" for NetBSD/sparc64 and fix typo.