freertos: Fix idf_additions.h include order error

When building for CONFIG_FREERTOS_SMP, "idf_additions.h" was previously
implicitly included by "task.h" so that other ESP-IDF components still have
access to IDF API additions without needing to include "idf_additions.h"
directly.

However, some FreeRTOS headers (e.g., queue.h) will include task.h before
declaring any types (e.g., QueueHandle_t). Thus if any of those types are used
in idf_additions.h, we get a missing type error.

This commit moves the implicity include of idf_additions.h to FreeRTOS.h

components/freertos/FreeRTOS-Kernel-SMP/include/freertos/FreeRTOS.h

@@ -1391,4 +1391,11 @@ typedef StaticStreamBuffer_t StaticMessageBuffer_t;
 #endif
 /* *INDENT-ON* */
 
+/* IDF API additions have been moved to idf_additions.h when building for
+ * Amazon SMP FreeRTOS. However, the rest of ESP-IDF has not been updated to
+ * include this header explicitly when calling this additional API. Thus, we
+ * include this here as a workaround until the rest of ESP-IDF can be updated
+ * to include idf_additions.h explicitly. */
+#include "freertos/idf_additions.h"
+
 #endif /* INC_FREERTOS_H */