[ofw] [IBBUS] Change BFI --> HCA GUID binding from late to early in fdo_start()

[Sean Hefty]

>-       BUS_PRINT(BUS_DBG_PNP,
>-                               ("%s exit %x\n",p_bfi->whoami,status));
>-       BUS_EXIT( BUS_DBG_PNP );
>+       /* bind BFI to HCA by CA GUID */
>+       p_bfi->ca_guid = ((const ci_interface_t*)&p_ext->hca_ifc.Verbs)->guid;

A cast is unnecessary here.