[armel] broken configure check cannot detect endianness

see https://launchpad.net/ubuntu/+source/sunpinyin/2.0.2-0ubuntu1/+build/1949870

scons: Reading SConscript files ...
Checking for pkg-config... yes
Checking for sqlite3... yes
Checking for C header file assert.h... yes
Checking for C function bind_textdomain_codeset()... yes
Checking for C function dcgettext()... yes
Checking for C header file dlfcn.h... yes
Checking for C function exp2()... no
Checking for C header file fcntl.h... yes
Checking for C header file getopt.h... yes
Checking for C function getopt_long()... yes
Checking for C function getpagesize()... yes
Checking for C function get_opt()... no
Checking for C header file iconv.h... yes
Checking for C header file inttypes.h... yes
Checking for C header file locale.h... yes
Checking for C header file libintl.h... yes
Checking for C header file limits.h... yes
Checking for C header file locale.h... yes
Checking for C function log2()... no
Checking for C header file memory.h... yes
Checking for C function memset()... yes
Checking for C function mmap()... yes
Checking for C function munmap()... yes
Checking for C function setlocale()... yes
Checking for C function strndup()... yes
Checking for C header file sys/mman.h... yes
Checking for C header file sys/param.h... yes
Checking for C header file sys/stat.h... yes
Checking for C header file sys/types.h... yes
Checking for C header file unistd.h... yes
Checking for C header file wchar.h... yes
scons: done reading SConscript files.
scons: Building targets ...
g++ -o src/portability.o -c -O2 -pipe -DHAVE_CONFIG_H -DSUNPINYIN_DATA_DIR='"/usr/local/lib/sunpinyin/data"' -I. -Isrc -Isrc/ime-core -Isrc/slm -Isrc/slm/slmseg -Isrc/slm/ids2ngram -Isrc/slm/slmbuild -Isrc/slm/slminfo -Isrc/slm/tools -Isrc/slm/mmseg -Isrc/slm/thread -Isrc/slm/tslminfo -Isrc/slm/tslmpack -Isrc/slm/slmprune -Isrc/slm/getWordFreq -Isrc/slm/tslmendian -Isrc/config -Isrc/pinyin -Isrc/lexicon src/portability.cpp
In file included from src/portability.cpp:39:
./config.h:93: error: #error can not detect the endianness!
scons: *** [src/portability.o] Error 1
scons: building terminated because of errors.
make: [build-stamp] Error 2 (ignored)