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

memmem(3): empty little string matches the beginning of the big string

This function originated in glibc, and this matches their behaviour
(and NetBSD, OpenBSD, and musl).

An empty big string (arg "l") is handled by the existing
l_len < s_len test.

Reviewed by: bapt, ngie
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D2657

- ANSIfy function definitions
- use nul when we are looking for a terminating character where appropriate

Approved by: imp

Add the function memmem(3) as found in glibc and others.
It is the binary equivalent to strstr(3).

void *memmem(const void *big, size_t big_len,
const void *little, size_t little_len);

Submitted by: Pascal Gloor <pascal.gloor at spale.com>
MFC after: 3 days