Enlarge MAX_COMPOSITE_DEVICE_SUBDEVICES for windows

Some interfaces, e.g. Nuvoton's Nu-Link2 can have more subdevices than the limit defined by MAX_COMPOSITE_DEVICE_SUBDEVICES for windows.
Try to enlarge the limit to enable these interfaces.

Author: ccli8

src/mbed_os_tools/detect/windows.py

@@ -33,7 +33,7 @@
     import winreg
 
 
-MAX_COMPOSITE_DEVICE_SUBDEVICES = 5
+MAX_COMPOSITE_DEVICE_SUBDEVICES = 8
 MBED_STORAGE_DEVICE_VENDOR_STRINGS = [
     "ven_mbed",
     "ven_segger",