arm64: zynqmp: Enable 2 NAND chips for zc1751 dc2

This board contains 2 nand chips that's why enable this feature.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/configs/xilinx_zynqmp_zc1751_xm016_dc2_defconfig b/configs/xilinx_zynqmp_zc1751_xm016_dc2_defconfig
index f9e5605..052e266 100644
--- a/configs/xilinx_zynqmp_zc1751_xm016_dc2_defconfig
+++ b/configs/xilinx_zynqmp_zc1751_xm016_dc2_defconfig
@@ -57,6 +57,7 @@
 CONFIG_MTD_DEVICE=y
 CONFIG_NAND=y
 CONFIG_NAND_ARASAN=y
+CONFIG_SYS_NAND_MAX_CHIPS=2
 CONFIG_SPI_FLASH=y
 CONFIG_SPI_FLASH_BAR=y
 CONFIG_SPI_FLASH_SST=y