[platform] Update doxygen errors with example code comments

sg- · sg- · commit 6062ca74040c · 2017-04-26T09:13:34.000-05:00
diff --git a/platform/mbed_error.h b/platform/mbed_error.h
@@ -53,7 +53,7 @@
  * if(x >= 5) {
  *     error("expected x to be less than 5, but got %d", x);
  * }
- * #endcode
+ * @endcode
  */
 
 #ifdef __cplusplus
diff --git a/platform/mbed_wait_api.h b/platform/mbed_wait_api.h
@@ -41,6 +41,7 @@ extern "C" {
  *         wait(0.5);
  *     }
  * }
+ * @endcode
  */
 
 /** Waits for a number of seconds, with microsecond resolution (within
