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

Move duplicated code to print l2 cache config into the common code.

PL310 driver update:

- Add pl310.disable tunable to disable L2 cache altogether. In
order to make sure that it's 100% disabled we use cache event
counters for cache line eviction and read allocate events
and panic if any of these counters increased. This is purely
for debugging purpose
- Direct access DEBUG_CTRL and CTRL might be unavailable in
unsecure mode, so use platform-specific functions for
these registers
- Replace #if 1 with proper erratum numbers
- Add erratum 753970 workaround
- Remove wait function for atomic operations
- Protect cache operations with spin mutex in order to prevent race condition
- Disable instruction cache prefetch and make sure data cache
prefetch is enabled in OMAP4-specific intialization

Merging of projects/armv6, part 10

- Support for Texas Instruments SoCs:
- AM335x
- OMAP4

- Kernel configs, DTS for Beaglebone and Pandaboard

Submitted by: Ben Gray, Damjan Marion