two land mine bits

Noticed when investigating one of the killer reason bugs recently
reported:  a land mine explosion shouldn't create a concealed pit trap;
make a revealed pit instead.  And while testing that, I noticed that the
"Kaboom" message given when pushing a boulder onto a land mine was given
while the map still showed the boulder at its original location even
though it had actually been moved already.  It's a little odd that you
get hit by shrapnel at your original position--as if you're shoving the
boulder ahead of you and then pausing a moment before stepping into its
former location--but that's trickier to fix; sometimes you won't advance
due to there being multiple boulders present (in that case you evidently
do shove the boulder instead of performing a steady push, so maybe the
current behavior is fine as it is).

src/trap.c

@@ -1,4 +1,4 @@
-/*	SCCS Id: @(#)trap.c	3.4	2003/02/10	*/
+/*	SCCS Id: @(#)trap.c	3.4	2003/04/30	*/
 /* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
 /* NetHack may be freely redistributed.  See license for details. */
 
@@ -1208,6 +1208,7 @@ struct trap *trap;
 	/* caller may subsequently fill pit, e.g. with a boulder */
 	trap->ttyp = PIT;		/* explosion creates a pit */
 	trap->madeby_u = FALSE;		/* resulting pit isn't yours */
+	seetrap(trap);			/* and it isn't concealed */
 }
 
 #endif /* OVLB */