rfilter initialized to UNDEFINED.

src/role.c

@@ -769,7 +769,7 @@ const struct Align aligns[] = {
 static struct {
     boolean roles[SIZE(roles)];
     short mask;
-} rfilter;
+} rfilter = UNDEFINED;
 
 STATIC_DCL int NDECL(randrole_filtered);
 STATIC_DCL char *FDECL(promptsep, (char *, int));