dmaengine: tegra-apb: Use dev_get_drvdata()

In the tegra_dma_runtime_suspend/resume functions, the pdev structure
is not needed, and so just call dev_get_drvdata() to get the device
data structure.

Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>