continuation of #109595
pkgconfig was aliased in 2018, however, it remained in
all-packages.nix due to its wide usage. This cleans
up the remaining references to pkgs.pkgsconfig and
moves the entry to aliases.nix.
python3Packages.pkgconfig remained unchanged because
it's the canonical name of the upstream package
on pypi.
It's broken since the directfb 1.6.3 -> 1.7.6 update, commit
bb7138e9a9 ("directfb: Update to 1.7.6").
[...]
building libilixi_graphics_la-Surface.lo
CXX libilixi_graphics_la-Surface.lo
Surface.cpp: In member function 'void ilixi::Surface::setGeometry(int, int, int, int)':
Surface.cpp:157:44: error: in C++98 'r' must be initialized by constructor, not by '{...}'
DFBRectangle r = { x, y, width, height };
