buildx.sh: fix clean option

- fix the use of $mod_dir
  "build_dir/$mod_dir" was evaluated as "build_dir/ Python-2.7" as
  variable mod_dir has leading whitespace

- fix the path of x11_file_list.txt
pcsc smartcard fixes form 64 bit from Ken
pcsc, add hexdump for debugging
Update faq-compile.txt
Merge pull request #139 from metalefty/devel

buildx.sh: fix clean option