r.texture: use standardized options (https://trac.osgeo.org/grass/ticket/2409)

git-svn-id: https://svn.osgeo.org/grass/grass/trunk@63062 15284696-431f-4ddb-bdfa-cd5b030d7da7

raster/r.texture/main.c

@@ -110,11 +110,7 @@ int main(int argc, char *argv[])
 
     opt_input = G_define_standard_option(G_OPT_R_INPUT);
 
-    opt_output = G_define_option();
-    opt_output->key = "prefix";
-    opt_output->type = TYPE_STRING;
-    opt_output->required = YES;
-    opt_output->description = _("Prefix for output raster map(s)");
+    opt_output = G_define_standard_option(G_OPT_R_BASENAME_OUTPUT);
 
     opt_size = G_define_option();
     opt_size->key = "size";