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

Mechanically substitute flags from historic mbuf allocator with
malloc(9) flags within sys.

Exceptions:

- sys/contrib not touched
- sys/mbuf.h edited manually

Mark MALLOC_DEFINEs static that have no corresponding MALLOC_DECLAREs.

This means that their use is restricted to a single C file.

Use m_unshare()+m_copyback() instead of m_freem()+m_devget() to keep
original mbuf chain headers. It can be less efficient in some cases, but it
looks better then mess of copying headers into the nonempty chain.

Slightly simplify code.

Whitespace cleanup.

Checked with: cvs diff -b

A node that implements Predictor-1 compression for PPP.

Submitted by: Alexander Motin <mav alkar.net>