FL-339: cli diagnostic interface for power subsystem. (#256)

* Core, API: add externs for c++
* Makefile: improve debug speed, flash with openocd, cleanup f2 config
* Power: add cli diagnostic.
* Local: fix api hal externs
* Local: fix externs in main and flipper_hal
* F2: power state dump stabs
* Bootloader flashing with openocd
* F3: move bq drivers to libs
* temporary do not build drivers on local
* temporary do not build drivers on f2

Co-authored-by: aanper <mail@s3f.ru>

firmware/targets/api-hal-include/api-hal-vcp.h

@@ -4,6 +4,10 @@
 #include <stdint.h>
 #include <string.h>
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 /* Init VCP HAL
  * Allocates ring buffer and initializes state
  */
@@ -22,3 +26,7 @@ size_t api_hal_vcp_rx(uint8_t* buffer, size_t size);
  * @param size - buffer size
  */
 void api_hal_vcp_tx(uint8_t* buffer, size_t size);
+
+#ifdef __cplusplus
+}
+#endif