Debugprobe release v2.2.1

This release is a point release because unknown/stale submodule(s)
caused a regression with long UART TX strings that subsequently could
not be reproduced.

The build artifacts for this release were compiled on a Raspberry Pi 5
running Raspberry Pi OS (Debian 12) instead of Ubuntu 22.04 on amd64.

src/usb_descriptors.c

diff --git a/src/usb_descriptors.c b/src/usb_descriptors.c
index ae2911a..04278c9 100644
--- a/src/usb_descriptors.c
+++ b/src/usb_descriptors.c
@@ -48,7 +48,7 @@
 
     .idVendor           = 0x2E8A, // Pi
     .idProduct          = 0x000c, // CMSIS-DAP Debug Probe
-    .bcdDevice          = 0x0220, // Version 02.20
+    .bcdDevice          = 0x0221, // Version 02.21
     .iManufacturer      = 0x01,
     .iProduct           = 0x02,
     .iSerialNumber      = 0x03,