DMA: PL330: Remove controller clock enable/disable

The controller clock is being enabled/disabled in AMBA bus
infrastructre in probe/remove functions. Hence, its not required
at driver level probe/remove.

Signed-off-by: Inderpal Singh <inderpal.singh@linaro.org>
Tested-by: Chander Kashyap <chander.kashyap@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>