dist/tools/usb-serial: fix exception on missing entries [backport 2022.10]

[maribu]

Backport of #19011

Contribution description

For some TTY interfaces no DB entry exists, which is reflected by having a None in tty[key]. Trying to match a regex against None in turn resulted then in an exception.

This fixes the issue by treating a filter applied on a non-existing entry as not matching.

Testing procedure

With the following TTYs attached:

$ ./dist/tools/usb-serial/ttys.py

path	driver	vendor	model	model_db	serial	ctime	iface_num
/dev/ttyACM1	cdc_acm	Arduino (www.arduino.cc)	0042	Mega 2560 R3 (CDC ACM)	857353134333519002C1	10:43:21	0
/dev/ttyACM2	cdc_acm	NXP Semiconductors	LPC-LINK2 CMSIS-DAP V5.173	None	NRA1AQCQ	10:43:31	1
/dev/ttyACM0	cdc_acm	Valve Software	Steam Deck Controller	None	MEDA20927049	10:28:36	3

In master

$ ./dist/tools/usb-serial/ttys.py --vendor 'Arduino' --model-db 'Mega 2560'
Traceback (most recent call last):
  File "/home/maribu/Repos/software/RIOT/examples/default/../../dist/tools/usb-serial/ttys.py", line 229, in <module>
    print_ttys(sys.argv)
  File "/home/maribu/Repos/software/RIOT/examples/default/../../dist/tools/usb-serial/ttys.py", line 212, in print_ttys
    if tty["serial"] not in args.exclude_serial and filters_match(filters, tty):
                                                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/maribu/Repos/software/RIOT/examples/default/../../dist/tools/usb-serial/ttys.py", line 50, in filters_match
    if not regex.match(tty[key]):
           ^^^^^^^^^^^^^^^^^^^^^
TypeError: expected string or bytes-like object, got 'NoneType'

With this PR:

$ ./dist/tools/usb-serial/ttys.py --vendor 'Arduino' --model-db 'Mega 2560'

path	driver	vendor	model	model_db	serial	ctime	iface_num
/dev/ttyACM1	cdc_acm	Arduino (www.arduino.cc)	0042	Mega 2560 R3 (CDC ACM)	857353134333519002C1	10:43:21	0

Issues/PRs references

None

[riot-ci]

Murdock results

✔️ PASSED

75b8bc4 dist/tools/usb-serial: fix exception on missing entries

Success	Failures	Total	Runtime
1	0	1	55s

Artifacts

• Documentation preview

This only reflects a subset of all builds from https://ci-prod.riot-os.org. Please refer to https://ci.riot-os.org for a complete build for now.

[maribu]

Thx :)