fix(flash): Add support for querying hardware version on USB 3.0 ports

As noted in the linked commit (coming from pybricks/pybricksdev#98),
the hardware version can still be read even when the brick is plugged
into a USB 3.0 port.

Unforunately, the CRC packets likely cannot be salvaged this way -
the CRC request is longer than the CRC response and so the CRC value
is overwritten inside the brick.

Author: JakubVanek

src/bl_info.c

@@ -52,11 +52,13 @@ int bootloader_info(void)
 		return ERR_COMM;
 	}
 
-	// forbid looped-back packets (usb 3.0 bug; reply *is* required here)
-	if (reply->type == VM_SYS_RQ)
-		return ERR_USBLOOP;
+	// Looped-back packets (e.g. reply->type == VM_SYS_RQ) are acceptable.
+	// According to https://github.com/pybricks/pybricksdev/commit/81f310da54ff40092bb4166226f8d52f943404c5
+	// the issue is less severe than originally anticipated. Only a part
+	// of the response buffer is overwritten by the PC's request and
+	// in this case the version is preserved.
 
-	if (reply->type != VM_OK)
+	if (reply->type != VM_OK && reply->type != VM_SYS_RQ)
 	{
 		errno = reply->ret;
 		fputs("Operation failed.\nlast_reply=", stderr);