Add new all_video module.

	Add new all_video module.

	* grub-core/Makefile.am (moddep.lst): Make dependent on video.lst.
	* grub-core/Makefile.core.def (all_video): New module.
	* grub-core/genmoddep.awk: Generate dependency of all_video from
	video.lst.
	* grub-core/lib/fake_module.c: New file.
	* grub-core/normal/main.c (features): Add feature_all_video_module.
	* util/grub.d/00_header.in: Define locale_dir based on $prefix and
	don't do explicit search again.
	insmod all_video in load_video if available.