[ruby/io-console] Enable only interrupt bits on `intr: true`

https://github.com/ruby/io-console/commit/baaf929041

ext/io/console/console.c

@@ -188,7 +188,7 @@ set_rawmode(conmode *t, void *arg)
 #endif
 #ifdef ISIG
 	if (r->intr) {
-	    t->c_iflag |= BRKINT|IXON;
+	    t->c_iflag |= BRKINT;
 	    t->c_lflag |= ISIG;
 	}
 #endif

test/io/console/test_io_console.rb

@@ -364,6 +364,11 @@ defined?(PTY) and defined?(IO.console) and TestIO_Console.class_eval do
         assert_ctrl("#{cc.ord}", cc, r, w)
         assert_ctrl("#{cc.ord}", cc, r, w)
       end
+      if cc = ctrl["stop"]
+        assert_ctrl("#{cc.ord}", cc, r, w)
+        assert_ctrl("#{cc.ord}", cc, r, w)
+        assert_ctrl("#{cc.ord}", cc, r, w)
+      end
     end
   end