vt: Fix contents of paste buffer for newcons.

[• hselasky]

Summary

Trim all whitespace from end of line, except for last line and
only use '\r' to terminate the pasted lines as expected by TTY.

Submitted by: Ivan Quitschal <[e-mail]>
MFC after: 1 week
Sponsored by: NVIDIA Networking

[• hselasky]

Make sure to zero-fill the remainder of the paste buffer, which will be skipped during paste.

[emaste]

PR https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=263084

[• hselasky]

Use TCHAR_CHARACTER() to detect whitespace.

Pointed out by: Tomoaki AOKI

[• hselasky]

Fix some bugs.

1. TTY converts \r to \n and \n to \0 , so only emit \r for newline.
2. Use TCHAR macro when checking for NUL character.

[• hselasky]

Please test! Works fine here.

[• hselasky]

Keep trailing space on last line.

[junchoon_dec.sakura.ne.jp]

In D35552#806924, @hselasky wrote:

Keep trailing space on last line.

Worked "almost" as expected.

*No unneeded '\0' pasted.
*Proper newline.
*Pasted wanted last-line trailing space.
*But unfortunately, IDEOGRAPHIC (Full-width) SPACE (E38080,  U+3000) seems to be treated
 as regular character, not as space.

Anyway, thanks in advance!

[• hselasky]

Updated patch with support for more unicode word separators.

Patches will be split before commit.

[• hselasky]

Include all chunks.

[junchoon_dec.sakura.ne.jp]

In D35552#807231, @hselasky wrote:

Include all chunks.

Thanks!
Tested and worked just as intended.

*Trailing spaces only listed in switch() of tchar_is_word_separator() are deleted on non-last lines.
*Space (tried U+3000 only, though) before U+2007, which is not listed and untouched, on non-last line is sanely kept.

If any others having objection to handled spaces pop in, only the switch() part is needed to be re-considererd.
Right?