[M65] Serial port is mistaken for jtag and forces USB disconnect during jtag initialization

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Test Environment (required)
Platform: Linux, Ubuntu 24.04
Version:
MEGA65 Cross-Development Tool
Version: 20250430.18-HEAD-b9ea802
(most recent in GIT as of this ticket).
MEGA65 Platform: Mega65
ROM Release: 920412
Core Commit: 20250201.17,9af7efa

Describe the bug
Attempting to follow directions via https://retrocombs.com/mega65-usb-ttl to connect a DSD Tech SH-U09C USB to TTL serial adapter w/ an FTDI FT232RL chip causes M65 to hang when attempting to initate any commands.

Grabbing the source for m65.c and selectively disabling / and adding logging I was able to determine that m65 hangs at the invocation of m65.c main -> init_fpgatag -> get_deviceid -> init_ftdi -> sync_ftdi. I wasn't able to go further due to my lack of understanding in ref to the JTAG protocol.

Entering the device /dev/ttyUSB<#> specifically via, eg: m65 -F -l /dev/ttyUSB0 does function as expected.

To Reproduce
Steps to reproduce the behavior:

1. With the specified adapter, plug in.
2. A /dev/ttyUSB<#> device shows up in /dev/
3. Enter m65 -F
4. The usb device disconnects and m65 freezes.

Expected behavior
I would expect the M65 device not to hang and the USB port not to disconnect.

Screenshots
n/a

Additional context
Add any other context about the problem here.