MFC r359626: vt: avoid overrun when stride is not a multiple of bytes per pixel

The reporter is developing a frame buffer driver for hardware using
3 bytes per pixel, but a stride that's a multiple of 256. Previously
this resulted in writing beyond the end of each stride. On the last
row this attempted to write past the end of the frame buffer, triggering
the assertion in vt_fb_mem_wr1().

PR: 243533
Submitted by: Thomas Skibo

Revert r330897:

This was intended to be a non-functional change. It wasn't. The commit
message was thus wrong. In addition it broke arm, and merged crypto
related code.

Revert with prejudice.

This revert skips files touched in r316370 since that commit was since
MFCed. This revert also skips files that require $FreeBSD$ property
changes.

Thank you to those who helped me get out of this mess including but not
limited to gonzo, kevans, rgrimes.

Requested by: gjb (re)

Partial merge of the SPDX changes

These changes are incomplete but are making it difficult
to determine what other changes can/should be merged.

No objections from: pfg

MFC r303043:

Increase vt(4) framebuffer maximum size

PR: 210382
Approved by: re (gjb)