[libcpu] fix No memory higher than 1 GB is mapped

libcpu/aarch64/common/setup.c

@@ -237,14 +237,14 @@ void rt_hw_common_setup(void)
 
     /* To virtual address */
     fdt_ptr = (void *)(fdt_ptr - pv_off);
-
+#ifdef KERNEL_VADDR_START
     if ((rt_ubase_t)fdt_ptr + fdt_size - KERNEL_VADDR_START > SIZE_GB)
     {
         fdt_ptr = rt_ioremap_early(fdt_ptr + pv_off, fdt_size);
 
         RT_ASSERT(fdt_ptr != RT_NULL);
     }
-
+#endif
     rt_memmove((void *)(fdt_start - pv_off), fdt_ptr, fdt_size);
     fdt_ptr = (void *)fdt_start - pv_off;