Implement ESP_LOGx override option

Usable for library developers who write code not dependent on Arduino.
Adding 3 lines to the includes will permit their debug messages to be
visible in Arduino IDE or when enabled under IDF

Kconfig

@@ -66,6 +66,16 @@ config ARDUHAL_LOG_COLORS
         Enable ANSI terminal color codes in bootloader output.
         In order to view these, your terminal program must support ANSI color codes.
 
+config ARDUHAL_ESP_LOG
+    bool "Forward ESP_LOGx to Arduino log output"
+    default "n"
+    help
+        This option will redefine the ESP_LOGx macros to Arduino's log_x macros.
+        To enable for your application, add the follwing after your includes:
+        #ifdef ARDUINO_ARCH_ESP32
+        #include "esp32-hal-log.h"
+        #endif
+
 endmenu
 
 config AUTOCONNECT_WIFI

cores/esp32/esp32-hal-log.h

@@ -107,6 +107,22 @@ int log_printf(const char *fmt, ...);
 #define log_e(format, ...)
 #endif
 
+#ifdef CONFIG_ARDUHAL_ESP_LOG
+#include "esp_log.h"
+
+#undef ESP_LOGE
+#undef ESP_LOGW
+#undef ESP_LOGI
+#undef ESP_LOGD
+#undef ESP_LOGV
+
+#define ESP_LOGE(tag, ...)  log_e(__VA_ARGS__)
+#define ESP_LOGW(tag, ...)  log_w(__VA_ARGS__)
+#define ESP_LOGI(tag, ...)  log_i(__VA_ARGS__)
+#define ESP_LOGD(tag, ...)  log_d(__VA_ARGS__)
+#define ESP_LOGV(tag, ...)  log_v(__VA_ARGS__)
+#endif
+
 #ifdef __cplusplus
 }
 #endif

docs/esp-idf_component.md

 To use as a component of ESP-IDF
 =================================================
 
+## Installation
+
 - Download and install [esp-idf](https://github.com/espressif/esp-idf)
 - Create blank idf project (from one of the examples)
 - in the project folder, create a folder called components and clone this repository inside
@@ -55,3 +57,14 @@ To use as a component of ESP-IDF
         - If enabled, WiFi will start with the last known configuration
         - Else it will wait for WiFi.begin
 - ```make flash monitor``` will build, upload and open serial monitor to your board
+
+## Logging To Serial
+
+If you are writing code that does not require Arduino to compile and you want your `ESP_LOGx` macros to work in Arduino IDE, you can enable the compatibility by adding the following lines after your includes:
+
+    ```cpp
+    #ifdef ARDUINO_ARCH_ESP32
+    #include "esp32-hal-log.h"
+    #endif
+    ```
+

tools/sdk/include/config/sdkconfig.h

@@ -134,6 +134,7 @@
 #define CONFIG_MBEDTLS_KEY_EXCHANGE_DHE_RSA 1
 #define CONFIG_ESP32_WIFI_DYNAMIC_TX_BUFFER_NUM 32
 #define CONFIG_MBEDTLS_ECP_DP_BP256R1_ENABLED 1
+#define CONFIG_ARDUHAL_ESP_LOG 1
 #define CONFIG_MBEDTLS_ECP_DP_SECP224K1_ENABLED 1
 #define CONFIG_ESP32_DEFAULT_CPU_FREQ_MHZ 240
 #define CONFIG_MBEDTLS_HARDWARE_AES 1

tools/sdk/sdkconfig

@@ -126,6 +126,7 @@ CONFIG_ARDUHAL_LOG_DEFAULT_LEVEL_DEBUG=
 CONFIG_ARDUHAL_LOG_DEFAULT_LEVEL_VERBOSE=
 CONFIG_ARDUHAL_LOG_DEFAULT_LEVEL=1
 CONFIG_ARDUHAL_LOG_COLORS=
+CONFIG_ARDUHAL_ESP_LOG=y
 CONFIG_AUTOCONNECT_WIFI=
 CONFIG_AWS_IOT_SDK=
 CONFIG_BT_ENABLED=y