sse2 compiler flag only added if running on an x86 machine (Patch from Debian package).
sse2 compiler flag only added if running on an x86 machine (Patch from Debian package).

svn path=/trunk/libavg/; revision=5396

yyd01245/libavg,libavg/libavg,hoodie/libavg,scotty007/libavg,scotty007/libavg,th3infinity/libavg,libavg/libavg,th3infinity/libavg,yyd01245/libavg,hoodie/libavg,yyd01245/libavg,hoodie/libavg,scotty007/libavg,th3infinity/libavg,hoodie/libavg,libavg/libavg,th3infinity/libavg,yyd01245/libavg,libavg/libavg,scotty007/libavg