dm: core: Require users of devres to include the header

At present devres.h is included in all files that include dm.h but few
make use of it. Also this pulls in linux/compat which adds several more
headers. Drop the automatic inclusion and require files to include devres
themselves. This provides a good indication of which files use devres.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Anatolij Gustschin <agust@denx.de>
diff --git a/fs/ubifs/master.c b/fs/ubifs/master.c
index 5654d45..2740aae 100644
--- a/fs/ubifs/master.c
+++ b/fs/ubifs/master.c
@@ -12,6 +12,7 @@
 
 #include "ubifs.h"
 #ifdef __UBOOT__
+#include <dm/devres.h>
 #include <linux/compat.h>
 #include <linux/err.h>
 #include <ubi_uboot.h>