wifi: wilc1000: do not realloc workqueue everytime an interface is added

In the Linux kernel, the following vulnerability has been resolved:

wifi: wilc1000: do not realloc workqueue everytime an interface is added

Commit 09ed8bfc5215 ("wilc1000: Rename workqueue from "WILC_wq" to

"NETDEV-wq"") moved workqueue creation in wilc_netdev_ifc_init in order to

set the interface name in the workqueue name. However, while the driver

needs only one workqueue, the wilc_netdev_ifc_init is called each time we

add an interface over a phy, which in turns overwrite the workqueue with a

new one. This can be observed with the following commands:

for i in $(seq 0 10)

do

iw phy phy0 interface add wlan1 type managed

iw dev wlan1 del

done

ps -eo pid,comm|grep wlan

39 kworker/R-wlan0

98 kworker/R-wlan1

102 kworker/R-wlan1

105 kworker/R-wlan1

108 kworker/R-wlan1

111 kworker/R-wlan1

114 kworker/R-wlan1

117 kworker/R-wlan1

120 kworker/R-wlan1

123 kworker/R-wlan1

126 kworker/R-wlan1

129 kworker/R-wlan1

Fix this leakage by putting back hif_workqueue allocation in

wilc_cfg80211_init. Regarding the workqueue name, it is indeed relevant to

set it lowercase, however it is not attached to a specific netdev, so

enforcing netdev name in the name is not so relevant. Still, enrich the

name with the wiphy name to make it clear which phy is using the workqueue.