dmaengine: dw-edma: Skip cleanup procedure if no private data found

DW eDMA driver private data is preserved in the passed DW eDMA chip info
structure. If the probe fails or for some reason the passed info object
doesn't have the private data pointer initialized, halt the DMA device
cleanup procedure to prevent system crashes.

Link: https://lore.kernel.org/r/20230113171409.30470-23-Sergey.Semin@baikalelectronics.ru


Tested-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Signed-off-by: Lorenzo Pieralisi <lpieralisi@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Acked-by: Vinod Koul <vkoul@kernel.org>