rust: pci: implement the dma::Device trait

The PCI bus is potentially capable of performing DMA, hence implement
the `dma:Device` trait for `pci::Device`.

Signed-off-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Abdiel Janulgue <abdiel.janulgue@gmail.com>

Author: Danilo Krummrich

rust/kernel/pci.rs

@@ -432,3 +432,5 @@ impl AsRef<device::Device> for Device {
         &self.0
     }
 }
+
+impl crate::dma::Device for Device {}