[Iwlan] Replace HashMap with ConcurrentHashMap

Problem: ErrorPolicyManager tried to remove item while traversing
         the HashMap.
Solution: Use ConcurrentHashMap instead of HasMap.
          ConcurrentHashMap supports modification while traversing the
	  HasMap
Bug: 194911108
Test: Build and WFC tested
Change-Id: I16910f9adabb89f57a7ee93eba0bc7ce80166fc3
1 file changed