Remove $FreeBSD$: one-line sh pattern

Remove /^\s*#[#!]?\s*\$FreeBSD\$.*$\n/

pkgbase: Create a mlx-tools package

mlx* are only useful for users who have a Mellanox card.
Create a package for it so users that don't have this card can
avoid having this program.

Differential Revision: https://reviews.freebsd.org/D31795

Do a sweep and remove most WARNS=6 settings

Repeating the default WARNS here makes it slightly more difficult to
experiment with default WARNS changes, e.g. if we did something absolutely
bananas and introduced a WARNS=7 and wanted to try lifting the default to
that.

Drop most of them; there is one in the blake2 kernel module, but I suspect
it should be dropped -- the default WARNS in the rest of the build doesn't
currently apply to kernel modules, and I haven't put too much thought into
whether it makes sense to make it so.

Add kernel and userspace code to dump the firmware state of supported
ConnectX-4/5 devices in mlx5core.

The dump is obtained by reading a predefined register map from the
non-destructive crspace, accessible by the vendor-specific PCIe
capability (VSC). The dump is stored in preallocated kernel memory and
managed by the mlx5tool(8), which communicates with the driver using a
character device node.

The utility allows to store the dump in format
<address> <value>
into a file, to reset the dump content, and to manually initiate the
dump.

A call to mlx5_fwdump() should be added at the places where a dump
must be fetched automatically. The most likely place is right before a
firmware reset request.

Submitted by: kib@
MFC after: 1 week
Sponsored by: Mellanox Technologies