qcacld-3.0: Deregister NL MSG handlers during hdd_wlan_exit

Currently the NL MSG handlers for WLAN_NL_MSG_OEM and
WLAN_NL_MSG_SPECTRAL_SCAN are not deregistered during hdd_wlan_exit which
can causes a page fault if NL issues cld80211_doit for these NL messages
when the WLAN is not up.

Add Deregister APIs for all the NL MSGs to call as part of
hdd_exit_netlink_services during hdd_wlan_exit.

Change-Id: I5811dcfc79eff4ea7281de5f7591e078c572e69c
CRs-Fixed: 2232902
5 files changed