if_iwx: use net80211 suspend and resume methods

[thj]

Summary

Use net80211 suspend and resume methods when entering and leaving
suspend. Move the resume action outside of the IWX_LOCK.

Re-assert disabling the PCI timeout, this is copied from OpenBSD, but it
doesn't seem to hurt.

Test Plan

This lets me suspend and resume successfully many times. On resume I have to
kick iwx sometimes and trick it into letting traffic through, but I see this
pre-suspend on the same hardware so it is probably a different issue.

[adrian]

sys/dev/iwx/if_iwx.c

10679

I love how this keeps being copy/pasted from if_ath_pci.c :-)

[bz]

sys/dev/iwx/if_iwx.c

10692

I wonder if you just want to call iwx_init here and also reset the watchdog?
I also wonder if you should, in suspend, disable it as it'll likely fire as you come back?

[adrian]

I'm finally updating my GE76 w/ AX210 to test iwx and iwlwifi in -head out, so I'll have to apply this to actually get it to pass a suspend/resume pass. stay tuned!

[thj]

• Use iwx_init on resume

[thj]

sys/dev/iwx/if_iwx.c

10679

I found one instance where the value was 0x40 rather than 0x41 in the comment. I'm happy to carry this incantation if someone else was.

[adrian]

This doesn't apply cleanly on -head, it requires D49827 first

sys/dev/iwx/if_iwx.c

10689–10690

You're missing an IWX_UNLOCK() here in the error path (after iwx_stop_device())

[thj]

• iwx: unlock on error path
• create a diff that can be applied on main (sorry)

[adrian]

It's better than the status quo in -HEAD, so let's get it in and then churn some more on making it recover better!