sys: Automated cleanup of cdefs and other formatting

Apply the following automated changes to try to eliminate
no-longer-needed sys/cdefs.h includes as well as now-empty
blank lines in a row.

Remove /^#if.*\n#endif.*\n#include\s+<sys/cdefs.h>.*\n/
Remove /\n+#include\s+<sys/cdefs.h>.*\n+#if.*\n#endif.*\n+/
Remove /\n+#if.*\n#endif.*\n+/
Remove /^#if.*\n#endif.*\n/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/types.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/param.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/capsicum.h>/

Sponsored by: Netflix

sys: Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

arm/arm64 broadcom: Remove unused devclass arguments to DRIVER_MODULE.

arm: clean up empty lines in .c and .h files

Mark more nodes as CTLFLAG_MPSAFE or CTLFLAG_NEEDGIANT (17 of many)

r357614 added CTLFLAG_NEEDGIANT to make it easier to find nodes that are
still not MPSAFE (or already are but aren’t properly marked).
Use it in preparation for a general review of all nodes.

This is non-functional change that adds annotations to SYSCTL_NODE and
SYSCTL_PROC nodes using one of the soon-to-be-required flags.

Mark all obvious cases as MPSAFE. All entries that haven't been marked
as MPSAFE before are by default marked as NEEDGIANT

Approved by: kib (mentor, blanket)
Commented by: kib, gallatin, melifaro
Differential Revision: https://reviews.freebsd.org/D23718

[rpi] Add support for the second PWM channel

Add support for the second channel to bcm2835_pwm driver. Configurable
parameters like mode, period, ratio are exposed as sysctls with postfix '2',
e.g.: dev.pwm.N.mode2, dev.pwm.N.period2, dev.pwm.N.ratio2

Second channel can be enabled in DTB by configuring pwn-2chan overlay
instead of pwm in config.txt. See [1]

[1] https://github.com/raspberrypi/firmware/blob/master/boot/overlays/README

Submitted by: Bob Frazier
Differential Revision: https://reviews.freebsd.org/D15769

[pi] Do not attach bcm2835_pwm if DTB node is not enabled

Switch to standard FDT-base driver behavior and don't attach
if node "status" property value nn DTS is not set to "okay"

On RPi PWM by default is disabled, to enable it pwm.dtbo
from official repo[1] should be copied to overlays directory
on SD card FAT partition and "dtoverlay=pwm" line added to
config.txt. For more details see pwm overlay documentation[2]

sysutils/rpi-firmware port now includes overlays, so they
can be installed as a part of release image build.

[1] https://github.com/raspberrypi/firmware/tree/master/boot
[2] https://github.com/raspberrypi/firmware/blob/master/boot/overlays/README

No objections from: phk@

[rpi] Add fdt_pinctrl(4) support to Raspberry Pi GPIO driver

On Raspberry Pi platform GPIO controller also responsible for pins
multiplexing. Pi code predates proper FDT support in FreeBSD so a
lot of pinmux info is hardcoded. This patch:

- Implements pinctl methods in bcm2835_gpio
- Converts all devices with ad-hoc pinmux info to proper pin control
mechanisms and adds pinmux info in FreeBSD's custom dts files.
- Adds fdt_pinctrl option to RPI2 and RPI-B kernels
- Adds SPI pinmux config to FreeBSD's customization of GNU DTS.

Reviewed by: imp, manu
Differential Revision: https://reviews.freebsd.org/D14104

Forgot to edit copy&pasted copyright blurb.

Add a skeleton Clock Manager for RPi2/3, and use that from pwm
instead of frobbing the registers directly.

As a hack the bcm2835_pwm kmod presently ignores the 'status="disabled"'
in the RPI3 DTB, assuming that if you load the kld you probably
want the PWM to work.

Rename rpi_pwm to bcm283x_pwm, and build it on armv[67] and arm64.

Truncate ratio if period is lowered.

Tested on Rpi2 and Rpi3.

Rpi3 requires DTB->DTS->edit->DTB hack

Add a rudimentary PWM driver for the RaspberryPi.

Control is through sysctl, only GPIO12 supported.

bootverbose creates sysctls for direct mangling of relevant registers.

Only tested on RPI2