build: Make sure plist.pxd is included in tarballs
build: Make sure plist.pxd is included in tarballs

When generating a tarball on a system without cython installed,
plist.pxd was missing, causing build failures later on when trying to
use cython.
This seems to be caused by EXTRA_DIST being inside a if HAVE_CYTHON
block rather than being outside of it.

libimobiledevice-win32/libplist,Tatsh/libplist,libimobiledevice-win32/libplist,libimobiledevice-win32/libplist,libimobiledevice/libplist,libimobiledevice/libplist,Tatsh/libplist,Tatsh/libplist,Tatsh/libplist,libimobiledevice-win32/libplist,libimobiledevice/libplist