[uboot] porting cvitek asic chips:

1. add cvitek folders to u-boot-2021.10
	2. add cv183x/cv182x part
	3. add cv181x/cv180x part

Change-Id: I6dc2e5ff509dbab16bd60bfb3fd61852da5e01f6

u-boot-2021.10/arch/riscv/include/asm/u-boot-riscv.h

@@ -16,6 +16,7 @@ int cleanup_before_linux(void);
 
 /* board/.../... */
 int board_init(void);
+void board_save_time_record(uintptr_t saveaddr);
 void board_quiesce_devices(void);
 int riscv_board_reserved_mem_fixup(void *fdt);
 int riscv_fdt_copy_resv_mem_node(const void *src_fdt, void *dest_fdt);