Ath10k leaves AR9880 in a state that will not enumerate again when CPU warm booted

[David Dailey]

I discovered that this issue seems to follow at least 2 different
chipsets (AR9880 and AR9890) but doesn't happen with at least two BCM
chipsets.  And the enumeration failing after a warm boot doesn't
depend on ath10k loading at all.  Even with the module not present on
the system, the device doesn't enumerate after cold boot.  So it
appears this is something unique to the PCIe core on Atheros, not
ath10k.  I guess the only hope would be if somehow the unload of the
driver could restore the chipset back to a state where it would
enumerate again, but I don't have information on the chipset at that
level.

Dave