Update deep_sleep.rst (#850)

* Update deep_sleep.rst

Add description to enter deep sleep again without reset the node manually.

* Use full topic

Co-authored-by: Fabian Affolter <mail@fabian-affolter.ch>

components/deep_sleep.rst

@@ -111,7 +111,9 @@ Useful for
     it will no longer enter deep sleep mode and you can upload your OTA update.
 
     Remember to turn "OTA mode" off again after the OTA update by sending a MQTT message with the payload
-    ``OFF``. Note that the device won't enter deep sleep again until the next reboot.
+    ``OFF``. To enter the the deep sleep again after the OTA update send a message on the topic ``livingroom/sleep_mode`` 
+    with payload ``ON``. Deep sleep will start immediately. Don't forget to delete the payload before the node
+    wakes up again.
 
     .. code-block:: yaml
 
@@ -125,6 +127,10 @@ Useful for
             payload: 'ON'
             then:
               - deep_sleep.prevent: deep_sleep_1
+            topic: livingroom/sleep_mode
+            payload: 'ON'
+            then:
+              - deep_sleep.enter: deep_sleep_1
 
 See Also
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