Some drivers (e.g. AMD GFX8-) don't support explicit format modifiers. On these drivers, gbm_bo_create_with_modifiers() will fail. This results in "Error getting buffer" in the logs later on with all X11 windows staying invisible.
Fallback to the modifier-less API gbm_bo_create() in that case.
Signed-off-by: Simon Ser email@example.com