If calling `ch_strerror` with some values returns `NULL` which makes
the `GError` not get populated.
```
0 0x00007f252d64d3bd in fu_colorhug_device_attach (device=0x560d7b5c4520 [FuColorhugDevice], error=0x7ffc57a51040) at ../plugins/colorhug/fu-colorhug-device.c:200
1 0x0000560d7a398279 in fu_device_attach (self=0x560d7b5c4520 [FuColorhugDevice], error=0x7ffc57a51040) at ../src/fu-device.c:1988
2 0x0000560d7a3a4b6c in fu_plugin_device_attach (self=0x560d7b57e160 [FuPlugin], device=0x560d7b5c4520 [FuColorhugDevice], error=0x7ffc57a51040) at ../src/fu-plugin.c:856
3 0x0000560d7a3a553f in fu_plugin_runner_device_generic
(self=0x560d7b57e160 [FuPlugin], device=0x560d7b5c4520 [FuColorhugDevice], symbol_name=0x560d7a3d4258 "fu_plugin_update_attach", device_func=0x560d7a3a4ac1 <fu_plugin_device_attach>, error=0x7ffc57a51040) at ../src/fu-plugin.c:1049
4 0x0000560d7a3a618d in fu_plugin_runner_update_attach (self=0x560d7b57e160 [FuPlugin], device=0x560d7b5c4520 [FuColorhugDevice], error=0x7ffc57a51040) at ../src/fu-plugin.c:1333
5 0x0000560d7a3bcc33 in fu_engine_update
(self=0x560d7b4b9830 [FuEngine], device_id=0x560d7b64f200 "d45c9d222f7eeb3987c6a7674478bc6aec127b3f", blob_fw2=0x560d7b62c0d0, flags=FWUPD_INSTALL_FLAG_NONE, error=0x7ffc57a51150)
at ../src/fu-engine.c:2001
(gdb) print error_local
$1 = (GError_autoptr) 0x0
```
Currently ICL shows up like this:
```
├─Unknown Device:
│ Device ID: d066959bf1b0da600f4fcaab5aa31cab3ff05eee
│ Summary: Unmatched performance for high-speed I/O
│ Current version: 71.00
│ Update Error: Missing non-active nvmem
│ Flags: internal|require-ac|registered
│ GUID: e72e778e-94f7-5ed2-b560-1c1262ee217c
```
Which isn't very useful to end users. Instead show the generic name
`Thunderbolt Controller` which matches the behavior change we've made
in UEFI FW and Touchpad FW items too.
```
├─Thunderbolt Controller:
│ Device ID: d066959bf1b0da600f4fcaab5aa31cab3ff05eee
│ Summary: Unmatched performance for high-speed I/O
│ Current version: 71.00
│ Update Error: Missing non-active nvmem
│ Flags: internal|require-ac|registered
│ GUID: e72e778e-94f7-5ed2-b560-1c1262ee217c
```
Also, quite the messages about missing vid/did as these won't exist
on ICL either.
It turns out there is some bug in systemd v242 or less that runtime
directories can't be used. So only populate motd when we know that
we have a newer systemd
I saw a mention that they're actually CX21986 and had some on hand.
They do enumerate:
```
├─Pixel USB-C earbuds:
│ Device ID: 672c087de09848d9e7ee32aa1dea2fbeb8b81e6b
│ Summary: CX21986 USB audio device
│ Current version: 71.133.20
│ Bootloader Version: 03.01.00.00
│ Vendor: Google (USB:0x18D1)
│ Install Duration: 3 seconds
│ Flags: updatable|registered
│ GUIDs: d76048a5-ca69-5cb8-ac86-d418d70c5f29
│ 98043a29-72c5-549b-ad23-de4e2db20a14
│ 93279fe8-d478-531b-9637-05d026be3c2e
│ 8b71f776-f6d0-549d-9547-42740b24bbbc
```
Don't show output for all devices - it doesn't work for most of them.
I also found that running verify on my Synaptics touchpad device puts it
into a pretty bad state until reboot. That's of course a problem on
it's own, but at least prompting for it will prevent it from easily
happening.
I was seeing on a CML laptop with a Nuvoton TPM the following which
is definitely wrong:
```
Checksum: SHA1(791183aa2c4993dfaf75e95c91bdad067ac2cce1)
Checksum: SHA256(8a0656fe0024cc3300cc4dc8af4fc336112a51013aeb74b21c138ed116bb8691)
Checksum: SHA1(000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000)
```
Fixes a regression in 3d00522dd3 that caused systemd stopping to
not work.
Previously the flow was to use `GetUnit` and `StopUnit` on the manager
interface. In that code this was switched over it should have been
using the unit interface + `Stop` or manager interface + `StopUnit`
not try to use the manager interface on the unit proxy with `StopUnit`.
All of these messages continually output are just noise for unsupported
devices:
```
18:11:52:0851 FuPlugin using generic udev_device_added() on optionrom
18:11:52:0851 FuEngine optionrom ignoring: no FWUPD_GUID property
```
Actually trying to instantiate the object leads to:
Specified class size for type 'FuWacomEmrDevice' is smaller than the
parent type's 'FuWacomDevice' class size.
Fixes https://github.com/fwupd/fwupd/issues/1456
This was a new file format to help out an OEM, but they didn't actually use it.
If we do need it in the future, it would some back as a src/ helper, not in
plugins/dfu.
