ARM: 6132/1: PL330: Add common core driver

PL330 is a configurable DMA controller PrimeCell device.
The register map of the device is well defined.
The configuration of a particular implementation can be
read from the six configuration registers CR0-4,Dn.

This patch implements a driver for the specification:-
http://infocenter.arm.com/help/topic/com.arm.doc.ddi0424a/DDI0424A_dmac_pl330_r0p0_trm.pdf

The exported interface should be sufficient to implement
a driver for any DMA API.

Signed-off-by: Jassi Brar <jassisinghbrar@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>