Don't mention 'vc-stay-local' in the user manual

* doc/emacs/vc1-xtra.texi (CVS Options):
* doc/emacs/maintaining.texi (VC Directory Buffer): Remove
references to 'vc-stay-local', which no longer exists.
(Bug#30138)

doc/emacs/maintaining.texi

@@ -1206,11 +1206,9 @@ file.  RCS and SCCS show the name of the user locking a file as its
 status.
 
 @ifnottex
-@vindex vc-stay-local
-  On CVS and Subversion, the @code{vc-dir} command normally contacts
-the repository, which may be on a remote machine, to check for
-updates.  If you change the variable @code{vc-stay-local} or
-@code{vc-cvs-stay-local} (for CVS) to @code{nil} (@pxref{CVS
+  On CVS, the @code{vc-dir} command normally contacts the repository,
+which may be on a remote machine, to check for updates.  If you change
+the variable @code{vc-cvs-stay-local} to @code{nil} (@pxref{CVS
 Options}), then Emacs avoids contacting a remote repository when
 generating the VC Directory buffer (it will still contact it when
 necessary, e.g., when doing a commit).  This may be desirable if you

doc/emacs/vc1-xtra.texi

@@ -364,18 +364,13 @@ the name of the operation to invoke.
 @cindex remote repositories (CVS)
   When using a CVS repository on a remote machine, VC can try keeping
 network interactions to a minimum.  This is controlled by the variable
-@code{vc-cvs-stay-local}.  There is another variable,
-@code{vc-stay-local}, which enables the feature also for other back
-ends that support it, including CVS@.  In the following, we will talk
-only about @code{vc-cvs-stay-local}, but everything applies to
-@code{vc-stay-local} as well.
-
-  If @code{vc-cvs-stay-local} is @code{only-file} (the default), VC
-determines the version control status of each file using only the
-entry in the local CVS subdirectory and the information returned by
-previous CVS commands.  As a consequence, if you have modified a file
-and somebody else has checked in other changes, you will not be
-notified of the conflict until you try to commit.
+@code{vc-cvs-stay-local}.  If @code{vc-cvs-stay-local} is
+@code{only-file} (the default), VC determines the version control
+status of each file using only the entry in the local CVS subdirectory
+and the information returned by previous CVS commands.  As a
+consequence, if you have modified a file and somebody else has checked
+in other changes, you will not be notified of the conflict until you
+try to commit.
 
   If you change @code{vc-cvs-stay-local} to @code{nil}, VC queries the
 remote repository @emph{before} it decides what to do in