pbio/version: bump to v4.0.0-alpha.0

We plan on calling the next release v4. The main purpose of changing
this now is so that the WebUSB BOS descriptors will point to
labs.pybricks.com instead of code.pybricks.com.

Also fix missing include in usb_common_desc.c to make this actually
take effect.

Author: dlech

lib/pbio/drv/usb/usb_common_desc.c

@@ -8,6 +8,8 @@
 
 #if PBDRV_CONFIG_USB
 
+#include <pbio/version.h>
+
 #include "usb_common_desc.h"
 
 #if PBIO_VERSION_LEVEL_HEX == 0xA

lib/pbio/include/pbio/version.h

@@ -14,16 +14,16 @@
 #include <pbio/util.h>
 
 /** The current major version. */
-#define PBIO_VERSION_MAJOR 3
+#define PBIO_VERSION_MAJOR 4
 
 /** The current minor version. */
-#define PBIO_VERSION_MINOR 6
+#define PBIO_VERSION_MINOR 0
 
 /** The current patch version. */
-#define PBIO_VERSION_MICRO 1
+#define PBIO_VERSION_MICRO 0
 
 /** The current prerelease level as a hex digit. */
-#define PBIO_VERSION_LEVEL_HEX 0xF
+#define PBIO_VERSION_LEVEL_HEX 0xA
 
 /** The current prerelease serial. */
 #define PBIO_VERSION_SERIAL 0