window: Fix remaining references to the egl image surface type
window: Fix remaining references to the egl image surface type

Didn't catch these before, was compiling with sw cairo.

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