Copy stable/11@r303970 to releng/11.0 as part of the 11.0-RELEASE
cycle.

Prune svn:mergeinfo from the new branch, and rename it to RC1.

Update __FreeBSD_version.

Use the quarterly branch for the default FreeBSD.conf pkg(8) repo and
the dvd1.iso packages population.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Rename alloc_unr(9) to unr(9) and adjust the links accordingly.

MFC after: 3 weeks

Extend the kernel unit number allocator for allocating specific unit
numbers. This change adds a new function alloc_unr_specific() which
returns the requested unit number if it is free. If the number is
already allocated or out of the range, -1 is returned.

Update alloc_unr(9) manual page accordingly and add a MLINK for
alloc_unr_specific(9).

Discussed on: freebsd-hackers

Correct arguments to free_unr(), "item" was missing.

MFC after: 1 week

s/5.5/6.0/ in HISTORY section.

Discussed with: ru

(Mostly) markup fixes.

Approved by: re (blanket)

Manpage for unit allocator functions.

Reviewed by: phk