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

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

linuxkpi: Define ENOKEY to 126.

This is the same error code as Linux. This value is unused on FreeBSD.

Reviewed by: manu
Approved by: manu
Differential Revision: https://reviews.freebsd.org/D38149

linuxkpi: Define EBADSLT to 57

This is the same error code as Linux.

As emaste@ noted in the review, FreeBSD defines the following errno
values in `sys/errno.h`:
* 56 is `EISCONN`
* 57 is `ENOTCONN`

Reviewed by: manu
Approved by: manu
Differential Revision: https://reviews.freebsd.org/D37935

linuxkpi: errno: Add EHWPOISON

Needed by drm-kmod.

Reviewed by: bz, hselasky
Obtained from: drm-kmod
Sponsored by: Beckhoff Automation GmbH & Co. KG
Differential Revision: https://reviews.freebsd.org/D36017

LinuxKPI: add more errno

Add ENOMEDIUM, ENOSR, and ELNRNG to linux/errno.h needed by drivers.

MFC after: 3 days
Reviewed by: hselasky
Differential Revision: https://reviews.freebsd.org/D34227

LinuxKPI: Constantly use _LINUXKPI_ prefix in include guards

MFC after: 1 week
Reviewed by: bz, emaste, hselasky, manu
Differential Revision: https://reviews.freebsd.org/D33562

LinuxKPI: add more linux-specific errno

Add ERFKILL and EBADE found in iwlwifi and brcmfmac wireless drivers.
While here add a comment above the block of error numbers above 500 to
document expectations.

Obtained-from: bz_iwlwifi
Sponsored-by: The FreeBSD Foundation
MFC-after: 2 weeks
Reviewed-by: hselasky, emaste
Differential Revision: https://reviews.freebsd.org/D29396

linuxkpi: Add EBADRQC to errno.h

This is used in the amdgpu driver from Linux 5.2

Sponsored-by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D24807

linuxkpi whitespace cleanup

Reviewed by: hselasky, markj
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D14807

The Linux error defines should all be positive, else frequently used
error code checks might fail. ERESTART is in the BSD world defined as
-1. While at it add more Linux error codes.

Obtained from: kmacy @
MFC after: 1 week
Sponsored by: Mellanox Technologies

Finish process of moving the LinuxKPI module into the default kernel build.

- Move all files related to the LinuxKPI into sys/compat/linuxkpi and
its subfolders.
- Update sys/conf/files and some Makefiles to use new file locations.
- Added description of COMPAT_LINUXKPI to sys/conf/NOTES which in turn
adds the LinuxKPI to all LINT builds.
- The LinuxKPI can be added to the kernel by setting the
COMPAT_LINUXKPI option. The OFED kernel option no longer builds the
LinuxKPI into the kernel. This was done to keep the build rules for
the LinuxKPI in sys/conf/files simple.
- Extend the LinuxKPI module to include support for USB by moving the
Linux USB compat from usb.ko to linuxkpi.ko.
- Bump the FreeBSD_version.
- A universe kernel build has been done.

Reviewed by: np @ (cxgb and cxgbe related changes only)
Sponsored by: Mellanox Technologies