compositor-drm: fix EGL format type
compositor-drm: fix EGL format type

EGLInt is not always uint32_t so we need
to make sure we use the right int size for the format.

Signed-off-by: Alexandru DAMIAN <dca11ad146909de2e237c885165c72737f425f51@intel.com>

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