dmaengine: at_hdmac: use subsys_initcall instead of module_init

Use subsys_initcall instead of module_init in order to keep DMA engine rolling
before other peripheral drivers.
Signed-off-by: Eric Xu <hong.xu@atmel.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

drivers/dma/at_hdmac.c

@@ -1209,7 +1209,7 @@ static int __init at_dma_init(void)
 {
 	return platform_driver_probe(&at_dma_driver, at_dma_probe);
 }
-module_init(at_dma_init);
+subsys_initcall(at_dma_init);
 
 static void __exit at_dma_exit(void)
 {