Add support for the QCA6174 chip.

    T:  Bus=06 Lev=01 Prnt=01 Port=01 Cnt=02 Dev#=  3 Spd=12  MxCh= 0
    D:  Ver= 1.10 Cls=e0(wlcon) Sub=01 Prot=01 MxPS=64 #Cfgs=  1
    P:  Vendor=0489 ProdID=e078 Rev=00.01
    C:  #Ifs= 2 Cfg#= 1 Atr=e0 MxPwr=100mA
    I:  If#= 0 Alt= 0 #EPs= 3 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
    I:  If#= 1 Alt= 0 #EPs= 2 Cls=e0(wlcon) Sub=01 Prot=01 Driver=btusb
Signed-off-by: Anantha Krishnan <ananthk@codeaurora.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>