[PATCH] Add proper const keywords to sysctl(3) parameters.
This patch import several patches from FreeBSD, namely:
- r204170 which make use of const keywords where appropriate
- r240176 which avoid a segfault when the `name' argument is invalid
- r204172 & r244153 are cosmetics changes.
I did a build of world+kernel and install and it has running fine for several hours.
More tests and code reviews are welcome. In particular I am unsure of r240176 (how is `name' tested for "validity"?).