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

[nvram2env] fix nvram2env to scan all of memory, not 1/4th

The variable "size" stores number of words (4bytes). But the loop over
memory uses size as number of bytes to scan memory. As result it fetches
only 1/4th of memory.

This patch solves this problem and nvram2env fetches all NVRAM variables.

Test plan:

Pre-requisites: any MIPS board with ASCII-based NVRAM mapped into memory

* Add "device nvram2env" into kernel configuration
* Specify hints: base is mandatory (according to nvram2env(4))

hint.nvram.0.base=0x1c7f8000 (it's valid address for Asus RT-N53 with
flags = 0x4)

* Build & load kernel with bootverbose

Actual result: only part of nvram variables are found
Expected result: all variables are found

Submitted by: Michael Zhilin <mizhka@gmail.com>
Differential Revision: https://reviews.freebsd.org/D6466

Fix nvram2env after bus_space_fdt removal.

The generic bus space does the mapping now, no need to pre-translate
phys addresses to KSEG1 anymore.

Submitted by: Hiroki Mori

Convert remaining {g,s}etenv->kern_{g,s}etenv
left over from r273174.

Reported by: bz

Use DEVMETHOD_END macro defined in sys/bus.h instead of {0, 0} sentinel on device_method_t arrays

Reviewed by: cognet
Approved by: cognet

Import nvram2env, a device driver which imports various NVRAM-style
environments into the kernel environment.

The eventual aim is to replace these with specific drivers for
the various bootloaders (redboot, uboot, etc.) This however will
work for the time being until it can be properly addressed.

Submitted by: Aleksandr Rybalko <ray@dlink.ua>