Remove item about usleep macro name from todo file

In alt code where a call to usleep(3) is made to allow for configuring
speed originally I used the macro 'Z'. In one case 'Z' was already taken
so I changed it to 'S' for that entry. I had the thought it might be
nice to make it always the same. This however is not possible as more
entries already have 'S' used. Also it's not important since I changed
the Makefiles so that one can specify it like 'make clobber SLEEP=500
alt' or whatever, removing the macro name and having to mess with
'CDEFINE'.

tmp/things-todo.md

@@ -83,14 +83,6 @@ instead change it to make pull requests. See the
 requests rather than emailing judges. This can be done on the final pass of the
 files.
 
-- In the entries with the alt code that use `usleep(3)` make the macro name
-consistent across all entries. At one point `Z` was used but in one entry `Z`
-was taken so this would not work. It appears at this time (16 November 2023)
-that it might be that `S` will work in all cases (currently?) though one has two
-values so the second would could be changed to `SS` (which is convenient as it's
-for SDL). This is low priority but it would be nice to have done as it would
-make it consistent and easy to remember.
-
 - With the entries that we recommend the alt code first when it comes to it
 going too fast we should say not what it looks like in modern systems but rather
 what it LOOKED LIKE AT THE TIME. At Wed 22 Nov 2023 13:02:04 UTC the only entry