[glibc/maskray/clang] manual: Update _TIME_BITS to clarify it's user defined

[Fangrui Song <maskray@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=ad6feef1b0c2cc6d7ad29c5cc4e14ba16f360f06

commit ad6feef1b0c2cc6d7ad29c5cc4e14ba16f360f06
Author: Stafford Horne <shorne@gmail.com>
Date:   Fri Oct 15 06:55:31 2021 +0900

    manual: Update _TIME_BITS to clarify it's user defined
    
    The current language reads "This macro determines...", changing to
    "Define this macro...".  This is consistent with other feature macro
    documentation language.
    
    When I first read the previous language it seems to indicate that the
    macro is already defined.  By changing the language to "Define this
    macro..." it's clear that its the user's responsibility to define it.

Diff:
---
 manual/creature.texi | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/manual/creature.texi b/manual/creature.texi
index c13de52f1f..6193e0735c 100644
--- a/manual/creature.texi
+++ b/manual/creature.texi
@@ -171,8 +171,8 @@ This macro was introduced as part of the Large File Support extension
 @end defvr
 
 @defvr Macro _TIME_BITS
-This macro determines the bit size of @code{time_t}, and therefore the
-bit size of all @code{time_t}-derived types and the prototypes of all
+Define this macro to control the bit size of @code{time_t}, and therefore
+the bit size of all @code{time_t}-derived types and the prototypes of all
 related functions.
 
 @enumerate