vim-patch:8.2.3115: Coverity complains about free_wininfo() use

Problem:    Coverity complains about free_wininfo() use.
Solution:   Add a condition that "wip2" is not equal to "wip". (Neovim vim/vim#14996)
b5098060f4

This fix came from https://github.com/neovim/neovim/pull/14996.
This commit adds only a comment to be in sync with Vim.

N/A patches for version.c:

vim-patch:8.2.3063: crash when switching 'cryptmethod' to xchaha20 with undo file

Problem:    Crash when switching 'cryptmethod' to xchaha20 with an existing
            undo file. (Martin Tournoij)
Solution:   Disable reading undo file when decoding can't be done inplace.
            (issue vim/vim#8467)
65aee0b714

vim-patch:8.2.3101: missing function prototype for vim_round()

Problem:    Missing function prototype for vim_round().
Solution:   Add the prototype.
67b17a6fc6

vim-patch:8.2.3119: compiler warning for unused argument

Problem:    Compiler warning for unused argument.
Solution:   Add UNUSED.
6a9e5c69cf

vim-patch:8.2.3120: crypt with sodium test fails on MS-Windows

Problem:    Crypt with sodium test fails on MS-Windows.
Solution:   Make the tests pass. (closes vim/vim#8428)
db86472770

vim-patch:8.2.3131: MS-Windows: ipv6 channel test is very flaky in the GUI

Problem:    MS-Windows: ipv6 channel test is very flaky in the GUI.
Solution:   Skip the test.
981217c11f

vim-patch:8.2.3140: MS-Windows: ipv6 channel test is very flaky also without GUI

Problem:    MS-Windows: ipv6 channel test is very flaky also without the GUI.
Solution:   Skip the test also without the GUI.
482d2f37a5

vim-patch:8.2.3157: crypt test may fail on MS-Windows

Problem:    Crypt test may fail on MS-Windows.
Solution:   Ignore "[unix]" in the file message. (Christian Brabandt,
            closes vim/vim#8561)
16e26a3116

vim-patch:8.2.3218: when using xchaha20 crypt undo file is not removed

Problem:    When using xchaha20 crypt undo file is not removed.
Solution:   Reset 'undofile' and delete the file. (Christian Brabandt,
            closes vim/vim#8630, closes vim/vim#8467)
8a4c812ede

vim-patch:8.2.3245: the crypt key may appear in a swap partition

Problem:    The crypt key may appear in a swap partition.
Solution:   When using xchaha20 use sodium_mlock(). (Christian Brabandt,
            closes vim/vim#8657)
131530a54d

src/nvim/window.c

@@ -4662,6 +4662,7 @@ win_free (
 
         // If there already is an entry with "wi_win" set to NULL it
         // must be removed, it would never be used.
+        // Skip "wip" itself, otherwise Coverity complains.
         for (wip2 = buf->b_wininfo; wip2 != NULL; wip2 = wip2->wi_next) {
           // `wip2 != wip` to satisfy Coverity. #14884
           if (wip2 != wip && wip2->wi_win == NULL) {