Audit rloc()

Most of the time, rloc() is used for teleporting monsters and it's not a
big deal if they can't find somewhere to go. In a few cases, it is. I
went through all the callsites and made calls to rloc() not cause
impossible()s if they don't need to.

Fixes a bug/suite of bugs reported by ais523.

src/vault.c

@@ -614,7 +614,7 @@ register struct monst *grd;
             if (u_carry_gold) { /* player teleported */
                 m = grd->mx;
                 n = grd->my;
-                (void) rloc(grd, FALSE);
+                (void) rloc(grd, TRUE);
                 levl[m][n].typ = egrd->fakecorr[0].ftyp;
                 newsym(m, n);
                 grd->mpeaceful = 0;