xilinx: Introduce board_late_init_xilinx()

This function should keep common shared late configurations for Xilinx
SoCs.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/board/topic/zynq/Makefile b/board/topic/zynq/Makefile
index becadd2..cc100b0 100644
--- a/board/topic/zynq/Makefile
+++ b/board/topic/zynq/Makefile
@@ -1,6 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0+
 
 obj-y	:= board.o
+obj-y	+= ../../xilinx/common/board.o
 
 # Remove quotes
 hw-platform-y :=$(shell echo $(CONFIG_DEFAULT_DEVICE_TREE))