Revert r330897:

This was intended to be a non-functional change. It wasn't. The commit
message was thus wrong. In addition it broke arm, and merged crypto
related code.

Revert with prejudice.

This revert skips files touched in r316370 since that commit was since
MFCed. This revert also skips files that require $FreeBSD$ property
changes.

Thank you to those who helped me get out of this mess including but not
limited to gonzo, kevans, rgrimes.

Requested by: gjb (re)

Partial merge of the SPDX changes

These changes are incomplete but are making it difficult
to determine what other changes can/should be merged.

No objections from: pfg

MFC r327862

dhclient(8): add missing include

stdbool is technically needed, though we can get away without it due to
header pollution.

Pointy-hat-to: asomers

MFC r326834, r326853

r326834:
dhclient(8): Don't shift through the sign bit of a signed int

PR: 208007
Submitted by: Michael McConville <mmcco@mykolab.com>

r326853:
dhclient(8): raise WARNS to 3

Mostly had to fix a lot of signed/unsigned comparison warnings

Sponsored by: Spectra Logic Corp

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

In sbin/dhclient, since we know the size of the source strings anyway,
we might as well use memcpy; strlcpy is really unnecessary here.

MFC after: 1 week

In sbin/dhclient, work around warnings about the size argument to
strlcpy appearing to be the size of the source buffer, instead of the
destination.

MFC after: 1 week

Add __FBSDID to all .c files in dhclient to aid in determining file
versions when dealing with user problems.

NULL is not a valid time_t.

Submitted by: sam

This commit was generated by cvs2svn to compensate for changes in r147072,
which included commits to RCS files with non-trunk default branches.

Import the OpenBSD dhclient as shipped with OpenBSD-3.7 (the tag
OPENBSD_3_7).