Feature request: USB COM support

[hjnijlunsing]

Having the possibility of adding a USB COM and behave as regular COM1/COM2 port to PC's without Serial would get the following benefits to modern PC's:

• Ability to use Serial Midi solutions like SoftMPU and SBEMU
• Ability to play Dos games with two mice (Settlers - https://www.vogons.org/viewtopic.php?p=91695)
• Ability to debug projects (SBEMU) over serial port
• Ability to connect to wifi using ESP32 modems and Slirp
• Play dos games with 0-modem support

[crazii]

It could be done, EMM386 can be used to trap 3f8h etc.
but currently the port rapping was removed from Borland C/Watcom C build due to code size limit (that is not a problem now).
I need to reenable the code, also it needs adjustments for multiple code segments.