Use compositor->seat_list instead of a singular seat
Use compositor->seat_list instead of a singular seat

Signed-off-by: Daniel Stone <3d0f3b9ddcacec30c4008c5e030e6c13a478cb4f@fooishbar.org>

kwm81/weston,Gnurou/weston,eyolfson/weston,Tarnyko/weston-xdg_surface_present,mchalupa/weston,xorgy/weston,jonnylamb/weston,sir-murray/weston,Fantu/compositor-spice,eyolfson/weston,krezovic/weston,udoprog/weston,giucam/weston,krezovic/weston,sir-murray/weston,udoprog/weston,giucam/weston,mchalupa/weston,jonnylamb/weston,kwm81/weston,Tarnyko/weston-xdg_surface_present,xorgy/weston,Fantu/compositor-spice,Gnurou/weston,Fantu/compositor-spice