graphics/yagf: fix build with c++11, pet portlint

• fix build with c++11, errors like:

src/core/qipgrayscaleimage.cpp:168:19: error: non-constant-expression cannot be narrowed from type 'quint32' (aka 'unsigned int') to 'int' in initializer list [-Wc++11-narrowing]

IntRect r1 = {x1,y1,x2,(y1+y2)/2};

• pet portlint:
  • sort ONLY_FOR_ARCHS;
  • place ONLY_FOR_ARCHS earlier.

Reported by: pkg-fallout
MFH: 2018Q4