arm64: Add Xilinx ZynqMP support

Add basic Xilinx ZynqMP arm64 support.
Serial and SD is supported.
It supports emulation platfrom ep108 and QEMU.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/board/xilinx/zynqmp/MAINTAINERS b/board/xilinx/zynqmp/MAINTAINERS
new file mode 100644
index 0000000..da33340
--- /dev/null
+++ b/board/xilinx/zynqmp/MAINTAINERS
@@ -0,0 +1,6 @@
+XILINX_ZYNQMP BOARD
+M:	Michal Simek <michal.simek@xilinx.com>
+S:	Maintained
+F:	board/xilinx/zynqmp/
+F:	include/configs/xilinx_zynqmp.h
+F:	configs/xilinx_zynqmp_defconfig