freebsd-src loader: Correct terminal size

The UEFI spec says:

It is required that all output devices support at least 80x25 text mode. This mode is defined to be mode 0.

So change the EFI TEXT_ROWS macro to reflect this. This also makes it more inline with the BIOS version: https://github.com/freebsd/freebsd-src/blob/d19851f002862a5510bf31fae4083fab979258be/stand/i386/libi386/vbe.h#L136

Also clarify the man page. The only time we have a fixed resolution terminal is in text mode with the BIOS loader, and that uses 80x25. With the other configurations, the terminal size isn't really guaranteed to be anything.

Jun 15 '24 13:06 VexedUXR

A real vt100 is only 24 lines. This is commonly emulated like that.... but i know of almost no one that's so restrictive on the consoles they run. So we can live with that historical mismatch. While the successor terminals to the vt100 also had this limitation, the last time i heard of one connected to a FreeBSD machine was before smpng. And that was a gag....

Jun 15 '24 15:06 bsdimp

Looks good otherwise. Any chance you'd do sob lines for the commit?

Jun 15 '24 15:06 bsdimp

Sure. Was I supposed to do that for my other commits :/

Jun 15 '24 15:06 VexedUXR

Thanks for your contribution. My apologies that it took so long to land.

Jul 08 '24 23:07 bsdimp