dmaengine: dw-edma: Replace chip ID number with device name

Using an abstract number as the DW eDMA chip identifier isn't practical
because there can be more than one DW eDMA controller on the platform. Some
may be detected as the PCIe Endpoints, and others may be embedded in DW
PCIe Root Port/Endpoint controllers.  An abstract number in, for instance,
the IRQ handlers list, doesn't give a notion regarding their reference to
the particular DMA controller.

To preserve the code simplicity and support multi-eDMA platforms, use the
parental device name to create the DW eDMA controller name.

Link: https://lore.kernel.org/r/20230113171409.30470-22-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>