Diab's autotool'd version appears to put the files in the *right* places (PREFIX/bin PREFIX/lib PREFIX/include ... etc) , so I used a local prefix for building (${module_dir}/build) instead of using $SKA_ARCH_OS as the build prefix, and then copied the files out of the local build directory  and back in to the PGPLOT_DIR that we have used in the past. At some point, we might want to experiment with installing the files directly into SKA_ARCH_OS and eliminating the use of PGPLOT_DIR.