[BUGFIX] iwlwifi: trigger an uevent if CSR_GP_CNTRL 0xffffffff detected

We are seeing some platform issues that cause wifi NIC
to disappear from PCI bus.
Add an uevent for udev so it can run a script to make
pci rescan to bring the NIC back on.

type=bugfix
ticket=chrome-os-partner:35648315
fixes=unknown

Change-Id: Id566a180eb9998bf9e0d49e98a58ee34ee9e0415
Signed-off-by: Matt Chen <matt.chen@intel.com>
Reviewed-on: https://git-amr-3.devtools.intel.com/gerrit/151162
Tested-by: ec ger unix iil jenkins <EC.GER.UNIX.IIL.JENKINS@INTEL.COM>
Reviewed-by: Coelho, Luciano <luciano.coelho@intel.com>
x-iwlwifi-stack-dev: d88db40a9e221bce70930fbf26093083c8b6bda9
5 files changed