OpenOCD makefile integration and Charger IC initialization fixes. (#258)

* Makefile: start openocd from gdb, boot no boot version.
* bq25896: reset before readout. Cleanup.

bootloader/targets/f3/target.c

@@ -157,4 +157,4 @@ void target_switch2os() {
     LL_GPIO_ResetOutputPin(LED_RED_PORT, LED_RED_PIN);
     SCB->VTOR = BOOT_ADDRESS + OS_OFFSET;
     target_switch((void*)(BOOT_ADDRESS + OS_OFFSET));
-}
+}