Use unknown DST instead of standard time in timestamps

* lisp/ol.el (org-store-link): Prefer plain (encode-time ...)
to (apply 'encode-time ...), for speed.
* lisp/org-macs.el (org-parse-time-string): Return unknown DST,
not standard time.
* lisp/org.el (org-read-date-analyze): Return a timestamp with a DST
flag of -1 (unknown) rather than nil (standard time).

Max Nikulin:
A larger patch "Improve Org usage of timestamps" was suggested in
https://debbugs.gnu.org/cgi/bugreport.cgi?bug=54764#10

Changes selected for this patch normalizes timestamp format:
if it is a list than it should contain 9 elements to be compatible
with Emacs-27 and Emacs-28 `encode-time' single argument, nil should not
be used for DST field since it means standard time while actual value
is unknown and should be guessed.

Ignacio Casso reported a problem with agenda
https://list.orgmode.org/PAXPR06MB7760238F410CBE3203F78EE0C61E9@PAXPR06MB7760.eurprd06.prod.outlook.com
due to Emacs commit dd0727e1ec1 changing Org code.  It was mostly reverted
by 8ef37913d3 (bug#54731).  Code in the Org repository did not have
the bug, but it safer to add protection against similar refactoring.

lisp/ol.el

@@ -1618,9 +1618,7 @@ non-nil."
 	  (setq link
 		(format-time-string
 		 (car org-time-stamp-formats)
-		 (apply 'encode-time
-			(list 0 0 0 (nth 1 cd) (nth 0 cd) (nth 2 cd)
-			      nil nil nil))))
+		 (encode-time 0 0 0 (nth 1 cd) (nth 0 cd) (nth 2 cd))))
 	  (org-link-store-props :type "calendar" :date cd)))
 
        ((eq major-mode 'w3-mode)

lisp/org-macs.el

@@ -1415,7 +1415,7 @@ This should be a lot faster than the `parse-time-string'."
 	(string-to-number (match-string 4 s))
 	(string-to-number (match-string 3 s))
 	(string-to-number (match-string 2 s))
-	nil nil nil))
+	nil -1 nil))
 
 (defun org-matcher-time (s)
   "Interpret a time comparison value S as a floating point time.

lisp/org.el

@@ -13833,7 +13833,7 @@ user."
 	 (setq year (nth 5 org-defdecode))
 	 (setq org-read-date-analyze-forced-year t))))
     (setq org-read-date-analyze-futurep futurep)
-    (list second minute hour day month year)))
+    (list second minute hour day month year nil -1 nil)))
 
 (defvar parse-time-weekdays)
 (defun org-read-date-get-relative (s today default)