This isn't directly supported. However, for many purposes, the following will work:
1. Copy plink_common.c/plink_common.h and SFMT.c/SFMT.h into your source file directory.
2. Replace the '#include "zlib-1.2.8/zlib.h"' line in plink_common.h with '#include <zlib.h>'.
3. Add '#include "plink_common.h"' on top of any file using plink_common functions.
(Apologies in advance for any namespace conflicts caused by plink_common #defines.)