lirc-tools: fix build with host python3

Add an upstream patch making make_rel_symlink.py python3 compatible. Add
another patch that removes python3 dependency.

Fixes:
http://autobuild.buildroot.net/results/6c6/6c6e014a751650c16d25dfd3d673bd3199c72b2e/
http://autobuild.buildroot.net/results/857/85724dfd014cec5a80dd18a635826daa2edc1417/
http://autobuild.buildroot.net/results/a74/a74563f700a47065ffd1ba42c83c2d7722bacd89/



and many others.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>