Fixed icon cache NOP implementations

Signed-off-by: David Oberhollenzer <david.oberhollenzer@tele2.at>
[W32] Fixed D3D11 disable guards

Signed-off-by: David Oberhollenzer <david.oberhollenzer@tele2.at>
[W32] Fixed GL calling convention

Signed-off-by: David Oberhollenzer <david.oberhollenzer@tele2.at>