MAINTAINERS: Add myself as the DW eDMA driver reviewer

The driver original maintainer has been inactive for almost two years now.
It doesn't positively affect the new patches tests and reviews process.
Since the DW eDMA engine has been embedded into the PCIe controllers in
several our SoCs we will be interested in helping with the updates review.

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Acked-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20230511190902.28896-15-Sergey.Semin@baikalelectronics.ru
Signed-off-by: Vinod Koul <vkoul@kernel.org>