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

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

Fix the implementations of PSEUDO_NOERROR and PSEUDO.

The PSEUDO* macros should not declare <syscall>, only _<syscall> and
__sys_<syscall>. This was causing the interposing C wrappers to be
ignored due to link order.

Reviewed by: kib
Obtained from: CheriBSD (4e8e13c90fc6a80e1520de44a6864cfd78b3b56d)
MFC after: 1 week
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D4097

Fix PIC_RETURN when abicalls are not defined.

Submitted by: Artem Belevich (artemb at gmail dot com)

Merge jmallett@'s n64 work into HEAD - changeset 1.

Update libc assembly code to use macros that work on both o32 and n64.
Merge string functions from NetBSD.

The changes are from http://svn.freebsd.org/base/user/jmallett/octeon

Approved by: rrs (mentor), jmallett

Add mips support libc from the mips2-jnpr branch of perforce.