docs:Separate low-power documents

docs/en/api-guides/index.rst

@@ -42,3 +42,4 @@ API Guides
    :SOC_USB_SERIAL_JTAG_SUPPORTED: usb-serial-jtag-console
    :SOC_WIFI_SUPPORTED: wifi
    :SOC_WIFI_SUPPORTED: wifi-security
+   low-power-mode

docs/en/api-guides/low-power-mode.rst

@@ -0,0 +1,5 @@
+Low Power Mode User Guide
+==========================
+
+
+:link_to_translation:`zh_CN:[中文]`

docs/en/api-guides/wifi.rst

@@ -1752,6 +1752,8 @@ A config option :ref:`CONFIG_ESP_WIFI_11R_SUPPORT` and configuration parameter :
 {IDF_TARGET_NAME} Wi-Fi Power-saving Mode
 -----------------------------------------
 
+This subsection will briefly introduce the concepts and usage related to Wi-Fi Power Saving Mode, for a more detailed introduction please refer to the :doc:`Low Power Mode User Guide <../api-guides/low-power-mode>`
+
 Station Sleep
 ++++++++++++++++++++++