[Debian-med-packaging] Problem building mapsembler2 on several architectures: xmmintrin.h: No such file or directory

[Rebecca Palmer]

/usr/lib/gcc/x86_64-linux-gnu/4.9/include/xmmintrin.h only exists on x86 
because it provides direct access to x86-specific vector instructions. 
If the software in question already has a plain-C fallback, enable it; 
if it doesn't, keeping it x86-only is likely to be the only reasonable 
option.