在byte_order.h中增加对openwrt的aarch64的支持

[charliealexander73]

在树梅派上测试通过 在原文件39行的if的小端选择里面增加 defined(aarch64) 即可

if (defined(__BYTE_ORDER) && defined(__LITTLE_ENDIAN) && \

    __BYTE_ORDER == __LITTLE_ENDIAN) || \
defined(CPU_IA32) || defined(CPU_X64) || \
defined(__ia64) || defined(__ia64__) || defined(__alpha__) || defined(_M_ALPHA) || \
defined(vax) || defined(MIPSEL) || defined(_ARM_) || defined(__arm__) || defined(__aarch64__)

define CPU_LITTLE_ENDIAN

define IS_BIG_ENDIAN 0

define IS_LITTLE_ENDIAN 1

elif (defined(__BYTE_ORDER) && defined(__BIG_ENDIAN) && \

    __BYTE_ORDER == __BIG_ENDIAN) || \
defined(__sparc) || defined(__sparc__) || defined(sparc) || \
defined(_ARCH_PPC) || defined(_ARCH_PPC64) || defined(_POWER) || \
defined(__POWERPC__) || defined(POWERPC) || defined(__powerpc) || \
defined(__powerpc__) || defined(__powerpc64__) || defined(__ppc__) || \
defined(__hpux)  || defined(_MIPSEB) || defined(mc68000) || \
defined(__s390__) || defined(__s390x__) || defined(sel)

define CPU_BIG_ENDIAN

define IS_BIG_ENDIAN 1

define IS_LITTLE_ENDIAN 0

else

error "Can't detect CPU architechture"

endif