or1k: use Linux 5.4.x, fixes networking and strange xz decompress error

target/linux/Config.in.kernelversion

@@ -26,6 +26,7 @@ default ADK_TARGET_LINUX_KERNEL_VERSION_4_14 if ADK_TARGET_SYSTEM_QEMU_ARM_VERSA
 default ADK_TARGET_LINUX_KERNEL_VERSION_5_4 if ADK_TARGET_ARCH_CSKY
 default ADK_TARGET_LINUX_KERNEL_VERSION_5_4 if ADK_TARGET_ARCH_RISCV32
 default ADK_TARGET_LINUX_KERNEL_VERSION_5_4 if ADK_TARGET_ARCH_RISCV64
+default ADK_TARGET_LINUX_KERNEL_VERSION_5_4 if ADK_TARGET_ARCH_OR1K
 default ADK_TARGET_LINUX_KERNEL_VERSION_4_19
 
 config ADK_TARGET_LINUX_KERNEL_VERSION_GIT