board: Introduce xenguest_arm64 board

Introduce a minimal Xen guest board running as a virtual
machine under Xen Project's hypervisor [1], [2].

Part of the code is ported from Xen mini-os and also uses
work initially done by different authors from NXP: please see
relevant files for their copyrights.

[1] https://xenbits.xen.org
[2] https://wiki.xenproject.org/

Signed-off-by: Andrii Anisov <andrii_anisov@epam.com>
Signed-off-by: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Signed-off-by: Anastasiia Lukianenko <anastasiia_lukianenko@epam.com>
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 6b8a32c..bee626f 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1749,6 +1749,12 @@
 	bool "Support Cortina Presidio ASIC Platform"
 	select ARM64
 
+config TARGET_XENGUEST_ARM64
+	bool "Xen guest ARM64"
+	select ARM64
+	select XEN
+	select OF_CONTROL
+	select LINUX_KERNEL_IMAGE_HEADER
 endchoice
 
 config ARCH_SUPPORT_TFABOOT
@@ -1955,6 +1961,7 @@
 source "board/xilinx/zynq/Kconfig"
 source "board/xilinx/zynqmp/Kconfig"
 source "board/phytium/durian/Kconfig"
+source "board/xen/xenguest_arm64/Kconfig"
 
 source "arch/arm/Kconfig.debug"