#dipping from steed

Fix the reported bug of an unskilled rider who is unable to pick
items off the floor while mounted still being able to dip into water.
There might be other actions which need similar checking; this one only
handles the dip into pool/moat case.

src/steed.c

@@ -1,4 +1,4 @@
-/*	SCCS Id: @(#)steed.c	3.4	2002/09/08	*/
+/*	SCCS Id: @(#)steed.c	3.4	2002/10/10	*/
 /* Copyright (c) Kevin Hugo, 1998-1999. */
 /* NetHack may be freely redistributed.  See license for details. */
 
@@ -14,6 +14,13 @@ static NEARDATA const char steeds[] = {
 
 STATIC_DCL boolean FDECL(landing_spot, (coord *, int));
 
+/* caller has decided that hero can't reach something while mounted */
+void
+rider_cant_reach()
+{
+     You("aren't skilled enough to reach from %s.", y_monnam());
+}
+
 /*** Putting the saddle on ***/
 
 /* Can this monster wear a saddle? */