v.overlay: fix output layer handling (backport from trunk https://trac.osgeo.org/grass/changeset/69348)

git-svn-id: https://svn.osgeo.org/grass/grass/branches/releasebranch_7_0@69350 15284696-431f-4ddb-bdfa-cd5b030d7da7

vector/v.overlay/area_area.c

@@ -199,7 +199,7 @@ int area_area(struct Map_info *In, int *field, struct Map_info *Tmp,
 			if (Cats->field[i] == field[input]) {
 			    ATTR *at;
 
-			    Vect_cat_set(Centr[area].cat[input], ofield[input + 1],
+			    Vect_cat_set(Centr[area].cat[input], field[input],
 					 Cats->cat[i]);
 
 			    /* Mark as used */

vector/v.overlay/line_area.c

@@ -426,7 +426,7 @@ int line_area(struct Map_info *In, int *field, struct Map_info *Tmp,
 
 	    if (ofield[2] > 0 && field[1] > 0 && ofield[1] != ofield[2]) {
 		for (i = 0; i < ACats->n_cats; i++) {
-		    if (Cats->field[i] == field[1])
+		    if (ACats->field[i] == field[1])
 			Vect_cat_set(OCats, ofield[2], ACats->cat[i]);
 		}
 	    }