merge xterm 397.

merge xterm 392.

merge xterm 382.

merge libdrm 2.4.112, and xterm-372.

merge xauth 1.1.1 and xterm 370.

merge xterm 368 and libdrm 2.4.107.

merge xterm 367.

merge xterm-366. this includes the fix for CVE-2021-27135.

(note that testing so far has not revealed this problem on netbsd,
though i have not heard about pkgsrc x11 users.)

update for libXt 1.2.0 const/noreturnification:
- define GCC_* as supported by all our compilers
- mark xt_error as noreturn
- clear the error handler with XtSetErrorHandler(NULL) vs
((XtErrorHandler) 0) which avoids missing noreturn issue

initial import of xterm-330

initial import of xterm-327

initial import of xterm-318

initial import of xterm-308

initial import of xterm-303

initial import of xterm-293

initial import of xterm 271. important changes include:
add OPT_PRINT_ON_EXIT support for debugging X errors
adds an xterm+tmux terminfo entry
fix reverse video issues in the scroll bar
bold font suppression
updated desktop support

initial import of xterm 269:
- fixes/updates for fullscreen mode
- add "omitTranslation" resource
- removes some old defaults
- random bug fixes
- fixes for reverse mode
- fix for utf-8 problem, also our PR/44344

initial import of xterm 267. highlight:

- add copy-selection action

initial import of xterm-266

initial import of xterm 261. major changes include:

- many UTF8 fixes
- improve terminfo support
- better freedesktop.org integration
- lots and lots of bug fixes

initial import of xterm-248

import xterm-238

initial import of xterm-235