cleanup and added sync + async commands

comm/msg_responses.c

@@ -5,6 +5,7 @@
 #include "platform.h"
 #include "messages.h"
 #include "msg_responses.h"
+#include "payload_builder.h"
 
 void com_respond_snprintf(TF_ID frame_id, TF_TYPE type, const char *format, ...)
 {
@@ -37,6 +38,12 @@ void com_respond_ok(TF_ID frame_id)
     com_respond_buf(frame_id, MSG_SUCCESS, NULL, 0);
 }
 
+void com_send_pb(TF_TYPE type, PayloadBuilder *pb)
+{
+    uint32_t len;
+    uint8_t *buf = pb_close(pb, &len);
+    com_send_buf(type, buf, len);
+}
 
 void com_send_buf(TF_TYPE type, const uint8_t *buf, uint32_t len)
 {

comm/msg_responses.h

@@ -9,6 +9,8 @@
 #error "Include messages.h instead!"
 #endif
 
+#include "payload_builder.h"
+
 /**
  * Respond to a TF message using printf-like formatting.
  *
@@ -54,6 +56,14 @@ void com_respond_error(TF_ID frame_id, error_t error);
  */
 void com_send_buf(TF_TYPE type, const uint8_t *buf, uint32_t len);
 
+/**
+ * Send a payload builder's content
+ *
+ * @param type - response type byte
+ * @param pb - builder
+ */
+void com_send_pb(TF_TYPE type, PayloadBuilder *pb);
+
 /**
  * Same like tf_respond_buf(), but the buffer length is measured with strlen.
  * Used to sending ASCII string responses.