fix/bug-57080-mode-line-format-docs 4df872e5eea 1/5: Remove obsolete %t mode line construct documentation

[Phil Sainty]

branch: fix/bug-57080-mode-line-format-docs
commit 4df872e5eea11fc2bbc7827d2eafd1ad77f70d7d
Author: Phil Sainty <psainty@orcon.net.nz>
Commit: Phil Sainty <psainty@orcon.net.nz>

    Remove obsolete %t mode line construct documentation
    
    src/buffer.c (mode-line-format): Remove %t from docstring.
    
    This documentation had been previously removed in 1999 in [1]
    but was subsequently restored again in a different form in 2006
    in [2] as the construct was still supported on some systems.
    However it looks like it hasn't done what that documentation
    indicated since [3] in 2011, and the final remnant of this
    functionality was removed in [4] in 2013; so it seems clear that
    it's no longer supported and shouldn't be documented now.
    
    [1] commit 08de62001945d4dd32a3d6af44da05804cb296d5
    [2] commit dafbe726b89a36010f3f24bb1efe4ace0a5f7f0f
    [3] commit 05c652517317d10690aaf0a6aa0bc876382b9d82
    [4] commit 8549f9e89bd9288c4c709d183a5bf8f07dbeed3d
---
 src/buffer.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/buffer.c b/src/buffer.c
index df1f5206668..3bcd387f0c5 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -5143,7 +5143,6 @@ A string is printed verbatim in the mode line except for 
%-constructs:
   %P -- print percent of buffer above bottom of window, perhaps plus Top,
         or print Bottom or All.
   %n -- print Narrow if appropriate.
-  %t -- visited file is text or binary (if OS supports this distinction).
   %z -- print mnemonics of keyboard, terminal, and buffer coding systems.
   %Z -- like %z, but including the end-of-line format.
   %e -- print error message about full memory.