[tools] fix gen_modules_doc.py

properly check if module xml could be parsed
[modules] fix malformed xml files
[conf] remove outdated/unused firmware xml files
[usb_telemetry] Fixed fetching device serial number
[stm32] add usb_tunnel, cleanup setup makefile

also replace usb_tunnel_0 and usb_tunnel_1 on lpc with one usb_tunnel target with configurable uart
[stm32] usb_serial: check if connected in putchar and send

cleanup and rename VCOM_transmit_message to VCOM_send_message