Compilation fails on non-SSE platform

[vslotman]

I'm trying to cross-compile UpscaleDB for a Cortex A8, but this fails because the toolchain misses some headers required for SSE-instructions (which is logical, since the processor doesn't support SSE)

I have added '--disable-simd' to the configure-arguments, but the problem still occurs.

| Making all in unittests
| make[2]: Entering directory '/home/slotmv/pb/build/workspace/sources/upscaledb/unittests'
|   CXX      zint32.o
|   CXX      recovery.o
|   CXX      issue32.o
|   CXX      issue101.o
|   CXX      aes.o
|   CXX      issue43.o
|   CXXLD    issue32
| In file included from ../3rdparty/simdcomp/include/simdcomp.h:12:0,
|                  from zint32.cpp:25:
| ../3rdparty/simdcomp/include/simdbitpacking.h:10:23: fatal error: emmintrin.h: No such file or directory
|  #include <emmintrin.h>
|                        ^
| compilation terminated.