usb: use common pci dma alloc/mapping routines
usb: use common pci dma alloc/mapping routines

Signed-off-by: Nikunj A Dadhania <e2f4a5db9b4735182a88051d1e7a3599f9eac9db@linux.vnet.ibm.com>

open-power-host-os/slof,qemu/SLOF,open-power-host-os/slof,aik/SLOF,open-power-host-os/slof,stefanberger/SLOF-tpm,aik/SLOF,qemu/SLOF,qemu/SLOF,stefanberger/SLOF-tpm,stefanberger/SLOF-tpm,open-power-host-os/slof,aik/SLOF