Merge branch 'bugfix/clean_up_warnings' into 'master'

Clean up warnings and remove unused parts of FreeRTOS

For third party components (lwip and expat), compilation flags are adjusted to silence existing warnings (i have manually checked that all warnings are benign).
In components/esp32, replaced use of WIFI_DEBUG with ESP_LOG functions.

Additionally prvLockQueue/prvUnlockQueue have been removed, dragging some other bits of FreeRTOS along.

Original issue: https://github.com/espressif/esp-idf/issues/18

See merge request !111

components/esp32/cpu_start.c

@@ -44,8 +44,11 @@
 #include "esp_log.h"
 
 static void IRAM_ATTR user_start_cpu0(void);
+#if !CONFIG_FREERTOS_UNICORE
 static void IRAM_ATTR call_user_start_cpu1();
 static void IRAM_ATTR user_start_cpu1(void);
+static bool app_cpu_started = false;
+#endif
 extern void ets_setup_syscalls(void);
 extern esp_err_t app_main(void *ctx);
 #if CONFIG_BT_ENABLED
@@ -60,7 +63,6 @@ extern void (*__init_array_end)(void);
 extern volatile int port_xSchedulerRunning[2];
 
 static const char* TAG = "cpu_start";
-static bool app_cpu_started = false;
 
 /*
  * We arrive here after the bootloader finished loading the program from flash. The hardware is mostly uninitialized,
@@ -110,7 +112,7 @@ void IRAM_ATTR call_user_start_cpu0()
     user_start_cpu0();
 }
 
-
+#if !CONFIG_FREERTOS_UNICORE
 void IRAM_ATTR call_user_start_cpu1()
 {
     asm volatile (\
@@ -133,6 +135,7 @@ void IRAM_ATTR user_start_cpu1(void)
     ESP_LOGI(TAG, "Starting scheduler on APP CPU.");
     xPortStartScheduler();
 }
+#endif
 
 static void do_global_ctors(void)
 {