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/arch/riscv/lib/andes_plmt.c b/arch/riscv/lib/andes_plmt.c
index 84f4607..a7e90ca 100644
--- a/arch/riscv/lib/andes_plmt.c
+++ b/arch/riscv/lib/andes_plmt.c
@@ -13,6 +13,7 @@
 #include <syscon.h>
 #include <asm/io.h>
 #include <asm/syscon.h>
+#include <linux/err.h>
 
 /* mtime register */
 #define MTIME_REG(base)			((ulong)(base))