org-agenda: return multiple results when sexp return a string with "; "

* lisp/org.el (org-diary-sexp-entry): Split sexp result strings at semicolon.

When evaluating my %%(org-calendar-holidays) on October 31st, I got a
line like:

"Halloween; Daylight Saving Time Ends 3:00am (CEST)"

And it displays in calendar:
3:00 .... Halloween; Daylight Saving Time Ends (CEST)

This is wrong since Halloween is all day, not only at 3:00.

Splitting results on "; " allows to have an independant entry on each
event and displays things correctly.

Signed-off-by: Julien Danjou <julien@danjou.info>

lisp/org.el

@@ -15025,7 +15025,7 @@ D may be an absolute day number, or a calendar-type list (month day year)."
 			      (org-current-line)
 			      (buffer-file-name) sexp)
                      (sleep-for 2))))))
-    (cond ((stringp result) result)
+    (cond ((stringp result) (split-string result "; "))
 	  ((and (consp result)
 		(not (consp (cdr result)))
 		(stringp (cdr result))) (cdr result))