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

Add support for the uart classes to set their default register shift value.
This is needed with the pl011 driver. Before this change it would default
to a shift of 0, however the hardware places the registers at 4-byte
addresses meaning the value should be 2.

This patch fixes this for the pl011 when configured using the fdt. The
other drivers have a default value of 0 to keep this a no-op.

MFC after: 1 week

Move the uart_class definitions and fdt compat data into the individual
uart implementations, and export them using the new linker-set mechanism.

Differential Revision: https://reviews.freebsd.org/D1993
Submitted by: Michal Meloun

Use the FIFOs in the imx5/imx6 uart hardware instead of interrupting on
each byte sent or received.

Return the actual baud rate programmed in the hardware rather than 115200.
This allows the "3wire" entry in /etc/ttys (with no speed specified) to work.

Reword a comment block a bit; no functional changes.

Flesh out imx_uart_init() so that we're not relying on u-boot to init
the hardware (meaning uarts other than the console will work).

The freescale imx uart driver works for the whole i.MX family, so rename the
header file to not have "5xx" in the name.

Use a more professional device description.

Introduce grab and ungrab upcalls. When the kernel desires to grab the
console, it calls the grab functions. These functions should turn off
the RX interrupts, and any others that interfere. This makes mountroot
prompt work again. If there's more generalized need other than
prompting, many of these routines should be expanded to do those new
things.

Should have been part of r260889, but waasn't due to command line typo.

Reviewed by: bde (with reservations)

Fix crossed fingers output. Only comment changed.

Fix low-level uart drivers that set their fifo sizes in the softc too late.

uart(4) allocates send and receiver buffers in attach() before it calls
the low-level driver's attach routine. Many low-level drivers set the
fifo sizes in their attach routine, which is too late. Other drivers set
them in the probe() routine, so that they're available when uart(4)
allocates buffers. This fixes the ones that were setting the values too
late by moving the code to probe().

Integrate Efika MX project back to home.

Sponsored by: The FreeBSD Foundation