ARM: dts: sun4i: Add A10 SRAM and SRAM controller

The A10 has a few SRAM that can be mapped either to a device or to the CPU,
with the mapping being controlled by a SRAM controller.

Add the SRAM controller, the SRAM that it drives and the section that can
be used by the various devices.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Tested-by: Hans de Goede <hdegoede@redhat.com>

arch/arm/boot/dts/sun4i-a10-marsboard.dts

@@ -99,6 +99,10 @@
 	status = "okay";
 };
 
+&emac_sram {
+	status = "okay";
+};
+
 &emac {
 	pinctrl-names = "default";
 	pinctrl-0 = <&emac_pins_a>;