add lib32 because when building lib32-tcpreplay it's impossible to set --with-libpcap so that it would find both include files as well as the library in lib32 directory
maybe it would be beneficial to split --with-libpcap into --with-libpcap-includedir --with-libpcap-libdir as this already searches in the --with-libpcap value with and without any "lib" prefix, but include files always expect "include" dir there
${build_arch}-${host_os} lib/${build_arch}-${host_os} was later replaced with: lib/${MULTIARCH} ${MULTIARCH} and it was added to static library search as well
add lib32 because when building lib32-tcpreplay it's impossible to set --with-libpcap so that it would find both include files as well as the library in lib32 directory
maybe it would be beneficial to split --with-libpcap into --with-libpcap-includedir --with-libpcap-libdir as this already searches in the --with-libpcap value with and without any "lib" prefix, but include files always expect "include" dir there
most of this code was added in: https://github.com/appneta/tcpreplay/commit/202b8e82f9fd3c84ce5804577caeb36a33baabe7#diff-49473dca262eeab3b4a43002adb08b4db31020d190caaad1594b47f1d5daa810R570
then search for ${host_cpu} lib/${host_cpu} (without -${host_os} suffix) and ${build_arch}-${host_os} lib/${build_arch}-${host_os} was added, but only for search of dynamic library in: https://github.com/appneta/tcpreplay/commit/c3d5236563985a99f8bb02c3f1bd6950e3929047
${build_arch}-${host_os} lib/${build_arch}-${host_os} was later replaced with: lib/${MULTIARCH} ${MULTIARCH} and it was added to static library search as well
but for dynamic library it was searching in reversed order: ${MULTIARCH} lib/${MULTIARCH} https://github.com/appneta/tcpreplay/commit/ed9e3a818bde04813144014561e62f018c9eb85f
I don't think this reversed order was intentional, just unify all 4 cases to use the same directories in the same order