ARM: S5PV310: Add platform devices for PL330 DMACs

Samsung's Soc S5PV310 has three PL330 DMACs. First is dedicated for
Memory->Memory data transfer while the other two meant for data
transfer with peripherals.
Define and add latter two PL330 DMACs as platform devices on the
S5PV310 platform.

Signed-off-by: Jassi Brar <jassi.brar@samsung.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>