set default to false in create statement

this way existing users will be set to false instead of undef

share/schema_versions/App-Netdisco-DB-58-59-PostgreSQL.sql

@@ -1,7 +1,5 @@
 BEGIN;
 
-ALTER TABLE users ADD radius boolean;
-
-ALTER TABLE users ALTER radius SET DEFAULT false;
+ALTER TABLE users ADD COLUMN "radius" boolean DEFAULT false;
 
 COMMIT;