find correct base path when compiled as a library
find correct base path when compiled as a library

(this fixes errors about pci.ids in moongen)

emmericp/libmoon,libmoon/libmoon,emmericp/libmoon,emmericp/libmoon,scholzd/libmoon,scholzd/libmoon,scholzd/libmoon,libmoon/libmoon,libmoon/libmoon