v.extract: default layer to '1' (see https://trac.osgeo.org/grass/ticket/1081)

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@42420 15284696-431f-4ddb-bdfa-cd5b030d7da7

vector/v.extract/main.c

@@ -109,7 +109,7 @@ int main(int argc, char **argv)
 
     inopt = G_define_standard_option(G_OPT_V_INPUT);
 
-    fieldopt = G_define_standard_option(G_OPT_V_FIELD_ALL);
+    fieldopt = G_define_standard_option(G_OPT_V_FIELD);
     fieldopt->guisection = _("Selection");
     
     typopt = G_define_standard_option(G_OPT_V_TYPE);