Add warning addressable lights on esp-idf (#2989)

components/light/fastled.rst

@@ -20,6 +20,12 @@ FastLED Light
     - https://github.com/FastLED/FastLED/issues/1322
     - https://github.com/FastLED/FastLED/issues/1264
 
+.. warning::
+
+    FastLED does **not** work with ESP-IDF.
+
+    For addressable lights, you can use :doc:`esp32_rmt_led_strip`.
+
 .. _fastled-clockless:
 
 Clockless

components/light/neopixelbus.rst

@@ -5,6 +5,12 @@ NeoPixelBus Light
     :description: Instructions for setting up Neopixel addressable lights.
     :image: color_lens.svg
 
+.. warning::
+
+    NeoPixelBus does **not** work with ESP-IDF.
+
+    For addressable lights, you can use :doc:`esp32_rmt_led_strip`.
+
 The ``neopixelbus`` light platform allows you to create RGB lights
 in ESPHome for an individually addressable lights like NeoPixel or WS2812.