U77 - pits in drawbridges

dighole dealt with holes in drawbridges, but digactualhole did not

doc/fixes34.1

@@ -283,6 +283,7 @@ renamed debug commands: light sources -> lightsources,
 detect attempt to swap places with big pet through narrow opening
 stinking clouds in bones files do not get their ttl set reasonably
 stinking clouds in bones files may incorrectly set player_inside
+breaking wand of digging on a drawbridge shouldn't dig/hole a pit in the bridge
 
 
 Platform- and/or Interface-Specific Fixes

src/dig.c

@@ -504,6 +504,13 @@ int ttyp;
 	    breaksink(x, y);
 	    return;
 #endif
+	} else if (lev->typ == DRAWBRIDGE_DOWN ||
+		   (is_drawbridge_wall(x, y) >= 0)) {
+	    int bx = x, by = y;
+	    /* if under the portcullis, the bridge is adjacent */
+	    (void) find_drawbridge(&bx, &by);
+	    destroy_drawbridge(bx, by);
+	    return;
 	}
 
 	if (ttyp != PIT && !Can_dig_down(&u.uz)) {