openbsd: fix uv_cpu_info
openbsd: fix uv_cpu_info

Make sure the `uv_cpu_info_t` array is fully freed in case of error.
Also, make it more robust by setting `count` to `0` and `cpu_info` to
`NULL` in case of error, so a subsequent call to `uv_free_cpu_info()`
does not segfault.

Refs: https://github.com/libuv/libuv/issues/2068
PR-URL: https://github.com/libuv/libuv/pull/2432
Reviewed-By: Colin Ihrig <838f779c91673db29b8572ea3f54d191d3878ae2@gmail.com>
Reviewed-By: Anna Henningsen <2bc1ecb410e142bce83bce6f212b41e1781536dc@addaleax.net>
Reviewed-By: Ben Noordhuis <59bd0a3ff43b32849b319e645d4798d8a5d1e889@bnoordhuis.nl>
Reviewed-By: Saúl Ibarra Corretgé <8a7991f6950ea189abf159d6ec98d2fcc13dc5f6@gmail.com>

unknownbrackets/maxcso,unknownbrackets/maxcso,unknownbrackets/maxcso,unknownbrackets/maxcso,unknownbrackets/maxcso,unknownbrackets/maxcso,unknownbrackets/maxcso