Remove support for FreeBSD 7 and really old FreeBSD 8. The classifiers
have been in the base for a while, so the gymnastics here aren't
needed. In addition, the bugs in subr_disk.c have been fixed since
2009, so there's no need for an identical copy of it in the tree
anymore. There's really no need to binary patch g_io_request, so let's
get rid of the code (not compiled in anymore) lest others think it is
a good idea.


git-svn-id: svn+ssh://svn.freebsd.org/base/head@275947 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f
Remove comments relevant to 6.x only.


git-svn-id: svn+ssh://svn.freebsd.org/base/head@275948 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f