wlan: LIM: check add to null check dereference

Add code to check null dereference check.

Change-Id: I339f3aa9014b013f939179f22ed1650e8c3d6aed
Crs-Fixed: 667938
wlan: Fix static analysis issue(Buffer Overflow) in HDD

Fix Buffer Overflow Array Index Out of Boundsfound in static
analysis in HDD.In hdd_wmm_select_queue/hdd_hostapd_select_queue
skb->priority is assigned as enum which can have value 0 to 8,
we use global array hddLinuxUpToAcMap for up to ac mapping purpose,
which can take maximum index range from 0 to 7.As up (enum)
might be assgined up to 0-8(8 is SME_QOS_WMM_UP_MAX), so
we should check up before going for mapping to ac.

Change-Id: Ia2855cd0989fef44c55aa2b7af73f95ad0c5954a
CRs-Fixed: 689045