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

Remove /^\s*\*+\s*\$FreeBSD\$.*$\n/

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

SPDX: license IDs for some ISC-related files.

bhnd(4): extend the PMU APIs to support bwn(4)

The bwn(4) driver requires a number of extensions to the bhnd(4) PMU
interface to support external configuration of PLLs, LDOs, and other
parameters that require chipset or PHY-specific workarounds.

These changes add support for:

- Writing raw voltage register values to PHY-specific LDO regulator
registers (required by LP-PHY).
- Enabling/disabling PHY-specific LDOs (required by LP-PHY)
- Writing to arbitrary PMU chipctrl registers (required for common PHY PLL
reset support).
- Requesting chipset/PLL-specific spurious signal avoidance modes.
- Querying clock frequency and latency.

Additionally, rather than updating legacy PWRCTL support to conform to the
new PMU interface:

- PWRCTL API is now provided by a bhnd_pwrctl_if.m interface.
- Since PWRCTL is only found in older SSB-based chipsets, translation from
bhnd(4) bus APIs to corresponding PWRCTL operations is now handled
entirely within the siba(4) driver.
- The PWRCTL-specific host bridge clock gating APIs in bhnd_bus_if.m have
been lifted out into a standalone bhnd_pwrctl_hostb_if.m interface.

Approved by: adrian (mentor, implicit)
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D12664

bhnd(4): Implement common API for IOST/IOCTL register access and core reset


- Added bhnd(4) bus APIs for per-core ioctl/iost register access.
- Updated reset/suspend bhnd(4) APIs for compatibility with ioctl/iost
changes.
- Implemented core reset/suspend support for both bcma(4) and siba(4).
- Implemented explicit release of all outstanding PMU requests at the bus
level when putting a core into reset.

Approved by: adrian (mentor, implicit)
Differential Revision: https://reviews.freebsd.org/D8009

[mips/broadcom]: Replace static frequency table with generic PMU clock
handling.


- Extended PWRCTL/PMU APIs to support querying clock frequency during very
early boot, prior to bus attach.
- Implement generic PMU-based calculation of UART rclk values.
- Replaced use of static frequency tables (bcm_socinfo) with
runtime-determined values.

Approved by: adrian (mentor)
Differential Revision: https://reviews.freebsd.org/D7552

bhnd(4): Initial PMU/PWRCTL power and clock management support.


- Added bhnd_pmu driver implementations for PMU and PWRCTL chipsets,
derived from Broadcom's ISC-licensed HND code.
- Added bhnd bus-level support for routing per-core clock and resource
power requests to the PMU device.
- Lift ChipCommon support out into the bhnd module, dropping
bhnd_chipc.

Reviewed by: mizhka
Approved by: adrian (mentor)
Differential Revision: https://reviews.freebsd.org/D7492