staging: brcm80211: Remove abstraction of pci_(alloc/free)_consistent

The abstraction for allocating and freeing dma descriptor memory
has been removed and replaced by usage of pci_alloc_consistent and
pci_free_consistent.

Reviewed-by: Roland Vossen <rvossen@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>