Update man page that HS directory does not need to exist

changes/ticket20486

@@ -0,0 +1,3 @@
+  o Documentation (Onion Services):
+     - tor's man page incorrectly states that HiddenServiceDir must already
+       exist. This is not true. Fixes 20486.

doc/tor.1.txt

@@ -2334,9 +2334,9 @@ The following options are used to configure a hidden service.
 [[HiddenServiceDir]] **HiddenServiceDir** __DIRECTORY__::
     Store data files for a hidden service in DIRECTORY. Every hidden service
     must have a separate directory. You may use this option  multiple times to
-    specify multiple services. DIRECTORY must be an existing directory.
+    specify multiple services. If DIRECTORY does not exist, Tor will create it.
     (Note: in current versions of Tor, if DIRECTORY is a relative path,
-    it will be relative to current
+    it will be relative to the current
     working directory of Tor instance, not to its DataDirectory.  Do not
     rely on this behavior; it is not guaranteed to remain the same in future
     versions.)