Documentation/maintainer-tip: Clarify merge window policy

There are lots of maintainers "pings" during the merge window, even
for trivial patches.

Clarify that contributors should not expect progress on *any*
non-urgent patches during the merge window.  This applies to all
contributions, not just large ones.

Clarify the language around -rc1.  Trees really are closed during the
merge window.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/all/20240322183403.67BAEEFE%40davehans-spike.ostc.intel.com

Author: hansendc

Documentation/process/maintainer-tip.rst

@@ -409,20 +409,20 @@ See :ref:`resend_reminders`.
 Merge window
 ^^^^^^^^^^^^
 
-Please do not expect large patch series to be handled during the merge
-window or even during the week before.  Such patches should be submitted in
-mergeable state *at* *least* a week before the merge window opens.
-Exceptions are made for bug fixes and *sometimes* for small standalone
-drivers for new hardware or minimally invasive patches for hardware
-enablement.
+Please do not expect patches to be reviewed or merged by tip
+maintainers around or during the merge window.  The trees are closed
+to all but urgent fixes during this time.  They reopen once the merge
+window closes and a new -rc1 kernel has been released.
+
+Large series should be submitted in mergeable state *at* *least* a week
+before the merge window opens.  Exceptions are made for bug fixes and
+*sometimes* for small standalone drivers for new hardware or minimally
+invasive patches for hardware enablement.
 
 During the merge window, the maintainers instead focus on following the
 upstream changes, fixing merge window fallout, collecting bug fixes, and
 allowing themselves a breath. Please respect that.
 
-The release candidate -rc1 is the starting point for new patches to be
-applied which are targeted for the next merge window.
-
 So called _urgent_ branches will be merged into mainline during the
 stabilization phase of each release.