C++ bindings: remove duplicate empty line before enum setting functions
C++ bindings: remove duplicate empty line before enum setting functions

This was missing from isl-0.20-818-g7538ab42f1 (C++ bindings:
consistently print newline between method implementations,
Thu Dec 27 10:29:55 2018 +0100).

Signed-off-by: Sven Verdoolaege <dd860110a62b19214c4ee03aec0abffecb4e86b8@cerebras.net>

Meinersbur/isl,Meinersbur/isl,Meinersbur/isl,Meinersbur/isl