example: update led strip example with new rmt driver

examples/peripherals/rmt/led_strip/main/led_strip_encoder.h

@@ -0,0 +1,36 @@
+/*
+ * SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+#pragma once
+
+#include <stdint.h>
+#include "driver/rmt_encoder.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief Type of led strip encoder configuration
+ */
+typedef struct {
+    uint32_t resolution; /*!< Encoder resolution, in Hz */
+} led_strip_encoder_config_t;
+
+/**
+ * @brief Create RMT encoder for encoding LED strip pixels into RMT symbols
+ *
+ * @param[in] config Encoder configuration
+ * @param[out] ret_encoder Returned encoder handle
+ * @return
+ *      - ESP_ERR_INVALID_ARG for any invalid arguments
+ *      - ESP_ERR_NO_MEM out of memory when creating led strip encoder
+ *      - ESP_OK if creating encoder successfully
+ */
+esp_err_t rmt_new_led_strip_encoder(const led_strip_encoder_config_t *config, rmt_encoder_handle_t *ret_encoder);
+
+#ifdef __cplusplus
+}
+#endif