arm: prune imx5 support from the tree

[kevans]

Summary

The IMX5 configs were removed in advance of FreeBSD 14.0 in
cdb0c2a73df ("arm: Remove IMX5 specific kernel configs"). This code
isn't built with GENERIC and doesn't actually build today as-is, so
let's remove it to avoid needless maintenance work to it that won't be
tested. As usual, revival is welcome with a committed user and work to
maintain it with upstream DTS and, ideally, in GENERIC.

I note that vt_early_fb is now effectively orphaned as nothing else will
use it, but I haven't yet removed it since I have not done anything to
ascertain if it could be integrated easily enough for other SoC. It is
among the files that doesn't actually build with today's clang, though.

[imp]

+1 on keeping vt_early_fb for now. It's tiny and easy to gc later if no use is found for it.

[markmi_dsl-only.net]

https://www.freebsd.org/platforms/arm/ lists:

Freescale i.MX51, i.MX53, . . .

There are other things listed that might have questionable status (unsure), say Cores ARM9E, ARM10E, and ARM11J and Boards listing Raspberry Pi (no more to the text, so suggesting the original instead of, say, just armv7 and aarch64 vintages?) I've no clue if this list is intended to be forward/ongoing looking vs. listing everything the oldest support release handles, even those not handled by later releases.

[manu]

Thanks, this was my goal at the time to remove this code at some point after removing the kernel config but I never did it.