libsoup: add patch to fix build on hosts without Python 3.x

libsoup: add patch to fix build on hosts without Python 3.x

For no reason, the tld-parser.py script was changed from using
"python" to using "python3" in upstream commit
4b924e573da307436169d5ef7e04c0ab85b36ef9. This patch reverts this
change to fix the build of libsoup on systems that don't have Python
3.x installed. It avoids the need to add host-python3 as a dependency.

Furthermore, the tld-parser.py script has anyway been removed
upstream, and replaced by a dependency on a separate library providing
TLD information. Therefore, there is no risk of this particular script
becoming Python 3 only.

Fixes:

  http://autobuild.buildroot.net/results/91c2d6a1ca011787130db06695d6cd9e882f7258
  http://autobuild.buildroot.net/results/a318e595f02937534b3f8698ef4c04194a8b34af

Thanks to Asaf Kahlon <asafka7@gmail.com> for some initial
work/research on this build issue.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>