This patch adds LoongArch to the GRUB build system and various tools, so GRUB can be built on LoongArch as a UEFI application. Signed-off-by: Zhou Yang <zhouyang@loongson.cn> Signed-off-by: Xiaotian Wu <wuxiaotian@loongson.cn> Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>