arm64: defconfig: enable ZTE ZX related config

This patch enables the configuration for the ZTE ZX family.
Signed-off-by: NJun Nie <jun.nie@linaro.org>
Signed-off-by: NShawn Guo <shawnguo@kernel.org>

arch/arm64/configs/defconfig

@@ -54,6 +54,7 @@ CONFIG_ARCH_UNIPHIER=y
 CONFIG_ARCH_VEXPRESS=y
 CONFIG_ARCH_VULCAN=y
 CONFIG_ARCH_XGENE=y
+CONFIG_ARCH_ZX=y
 CONFIG_ARCH_ZYNQMP=y
 CONFIG_PCI=y
 CONFIG_PCI_MSI=y