dma: move dw_dmac driver to an own directory

The dw_dmac driver is going to be split into multiple files. To make this more
convenient move it to an own directory.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
diff --git a/MAINTAINERS b/MAINTAINERS
index 250dc97..e325809 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6990,8 +6990,7 @@
 M:	Viresh Kumar <viresh.linux@gmail.com>
 S:	Maintained
 F:	include/linux/dw_dmac.h
-F:	drivers/dma/dw_dmac_regs.h
-F:	drivers/dma/dw_dmac.c
+F:	drivers/dma/dw/
 
 SYNOPSYS DESIGNWARE MMC/SD/SDIO DRIVER
 M:	Seungwon Jeon <tgih.jun@samsung.com>