dmaengine: add a new helper dmaenginem_async_device_register

This patch adds the dmaenginem_async_device_register for DMA code.
Use the Devres to call the release for the DMA engine driver.

Signed-off-by: Huang Shijie <sjhuang@iluvatar.ai>
Signed-off-by: Vinod Koul <vkoul@kernel.org>
diff --git a/Documentation/driver-model/devres.txt b/Documentation/driver-model/devres.txt
index 7c1bb3d..43681ca 100644
--- a/Documentation/driver-model/devres.txt
+++ b/Documentation/driver-model/devres.txt
@@ -240,6 +240,7 @@
   devm_of_clk_add_hw_provider()
 
 DMA
+  dmaenginem_async_device_register()
   dmam_alloc_coherent()
   dmam_alloc_attrs()
   dmam_declare_coherent_memory()