simple-egl: Minor fix ups.
simple-egl: Minor fix ups.

1) Fix typo when initializing variables
2) Remove gratuitous glFlush() call
3) Localize shader program variable

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