ARM: dts: at91: Add dts files for at91sam9263ek

The device tree source files of at91sam9263ek boards are copied from
the Linux v4.10, do the changes as below.
 - Add the reg property for the pinctrl node.
 - Move the gpio (pioA, pioB, pioC, pioD, pioE) nodes as the pinctrl's
   slibling nodes, instead of the child nodes.
 - Add the "u-boot,dm-pre-reloc" property for the dbgu node are used
   in board_init_f stage.
 - Fix the compilation warnings.

Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/dts/Makefile b/arch/arm/dts/Makefile
index 916958e..02836f1 100644
--- a/arch/arm/dts/Makefile
+++ b/arch/arm/dts/Makefile
@@ -352,6 +352,8 @@
 	keystone-k2e-evm.dtb \
 	keystone-k2g-evm.dtb
 
+dtb-$(CONFIG_TARGET_AT91SAM9263EK) += at91sam9263ek.dtb
+
 dtb-$(CONFIG_TARGET_AT91SAM9RLEK) += at91sam9rlek.dtb
 
 dtb-$(CONFIG_TARGET_AT91SAM9260EK) += \