docs(observer): fix subject name in the example

docs/src/details/auxiliary-modules/observer/observer.rst

@@ -11,7 +11,7 @@ Overview
 
 .. _observer pattern:  https://en.wikipedia.org/wiki/Observer_pattern
 
-The ``lv_observer`` module is an implemention of the `Observer Pattern`_.
+The ``lv_observer`` module is an implementation of the `Observer Pattern`_.
 
 This implementation consists of:
 
@@ -69,7 +69,7 @@ A typical use case looks like this:
      * some_module.c
      *--------------*/
 
-    extern lv_subject_t some_subject;
+    extern lv_subject_t my_subject;
 
     // Will be called when Subject's value changes
     static void some_observer_cb(lv_observer_t * observer, lv_subject_t * subject)
@@ -81,19 +81,19 @@ A typical use case looks like this:
     void some_module_init(void)
     {
         // Subscribe to Subject as an Observer.
-        lv_subject_add_observer(&some_subject, some_observer_cb, NULL);
+        lv_subject_add_observer(&my_subject, some_observer_cb, NULL);
     }
 
     /*--------------
      * some_system.c
      *--------------*/
 
-    extern lv_subject_t some_subject;
+    extern lv_subject_t my_subject;
 
     void some_event(void)
     {
         // The below call sets Subject's value to 30 and notifies current Observers.
-        lv_subject_set_int(&some_subject, 30);
+        lv_subject_set_int(&my_subject, 30);
     }
 
 
@@ -228,7 +228,7 @@ both unsubscribes it from the Subject and deletes it from the LVGL heap.
 Subscribing While Associating Observer with a Widget
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-The function below assocates a Widget with an Observer while subscribing to a
+The function below associates a Widget with an Observer while subscribing to a
 Subject.  A copy of the pointer to that Widget is saved in the Observer's ``target``
 field.  This works exactly like the above method except that when the Widget is
 deleted, the Observer thus created will be automatically unsubscribed from the