drivers: uart: stm32: don't allow async TX on a suspended UART

[kamnxt]

Return an error if trying to send data using a suspended UART, instead of blocking, possibly forever, for a transmission that will never succeed.

Fixes #97063

[kamnxt]

Changed to -ECANCELED like in uart_nrfx_uarte2.c

zephyr/drivers/serial/uart_nrfx_uarte2.c

Lines 387 to 394 in bbfd206

	#if CONFIG_PM_DEVICE
	enum pm_device_state state;
	(void)pm_device_state_get(dev, &state);
	if (state != PM_DEVICE_STATE_ACTIVE) {
	return -ECANCELED;
	}
	#endif

[etienne-lms]

The change looks consistent to me. I think you need to rebase your change to successfully pass CI tests.

[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

[kamnxt]

... i guess i should probably change the commit name to have serial instead of uart? or is it fine?

I noticed some of the earlier commits that changed this driver used uart too, so I suppose that is ok?