libposixcompat: use explicit list of C files instead of glob
libposixcompat: use explicit list of C files instead of glob

Signed-off-by: Simon Gerber <13ba2e9de9ead0ea0b5f47504fb3a80bb9b1ee3b@inf.ethz.ch>

8l/barrelfish,kishoredbn/barrelfish,BarrelfishOS/barrelfish,BarrelfishOS/barrelfish,8l/barrelfish,kishoredbn/barrelfish,8l/barrelfish,BarrelfishOS/barrelfish,BarrelfishOS/barrelfish,BarrelfishOS/barrelfish,kishoredbn/barrelfish,BarrelfishOS/barrelfish,8l/barrelfish,kishoredbn/barrelfish,8l/barrelfish,kishoredbn/barrelfish,BarrelfishOS/barrelfish,8l/barrelfish,BarrelfishOS/barrelfish,BarrelfishOS/barrelfish,kishoredbn/barrelfish