patch 7.4.1890

Problem:    GUI: When channel data is received the cursor blinking is
            interrupted.  (Ramel Eshed)
Solution:   Don't update the cursor when it is blinking.

src/gui_mac.c

@@ -5114,6 +5114,11 @@ gui_mch_destroy_scrollbar(scrollbar_T *sb)
 #endif
 }
 
+    int
+gui_mch_is_blinking(void)
+{
+    return FALSE;
+}
 
 /*
  * Cursor blink functions.