drivers: serial: native_tty: config_get support

[vytvir]

This commit adds config_get support for native_tty. This is helpful as some driver code (e.g. u_blox m8) will error out if they can't read the current configuration.

[aescolar]

(Just for info) Related to #69101
CC @MarkoSagadin

[vytvir]

(Just for info) Related to #69101 CC @MarkoSagadin

Oh, didn't notice that.

[aescolar]

Thanks for the PR @vytvir.
Any reason to not just return the value provided during config?
(see discussion on the same topic here:
#69101 (review)
#69101 (comment)
#69101 (comment)
)

[vytvir]

Thanks for the PR @vytvir. Any reason to not just return the value provided during config? (see discussion on the same topic here: #69101 (review) #69101 (comment) #69101 (comment) )

From @dcpleung comment:

However, if the underlying hardware (in this case the underlying TTY) changes stuff on its own, it will be better to grab bits from the hardware so a proper and correct config can be programmed later.

This was my assumption too. I guess for the sake of completeness it's a nice-to-have, but not strictly neccecary?

That said, I just wanted the u_blox m8 driver to run without error'ing out. So I'm fine with either option.

[aescolar]

Thanks @vytvir just a few minor silly things.

[vytvir]

Requested changes by @aescolar completed.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[aescolar]

Suggested change

	int err = 0;
	err = errno;
	int err = errno;

Just saw this now, but you don't need to bother with it if you don't need to push again

[vytvir]

Hi @dcpleung , could you give this a review?