* grub-core/video/i386/pc/vbe.c (grub_vbe_bios_get_flat_panel_info):
New function.
(grub_vbe_bios_get_ddc_capabilities): Likewise.
(grub_vbe_bios_read_edid): Likewise.
(grub_vbe_edid_checksum): Likewise.
(grub_vbe_get_preferred_mode): Likewise. Try EDID followed by the
Flat Panel extension, in line with the X.org VESA driver.
(grub_video_vbe_setup): When the mode is "auto", try to get the
preferred mode from VBE, and use the largest mode that is no larger
than the preferred mode (some BIOSes expose a preferred mode that is
not in their mode list!). If this fails, fall back to 640x480 as a
safe conservative choice.
* include/grub/i386/pc/vbe.h (struct grub_vbe_flat_panel_info): New
structure.
(struct grub_vbe_edid_info): Likewise.
(grub_vbe_bios_get_flat_panel_info): Add prototype.
(grub_vbe_bios_get_ddc_capabilities): Likewise.
(grub_vbe_bios_read_edid): Likewise.
* util/grub.d/00_header.in (GRUB_GFXMODE): Default to "auto". This
is more appropriate on a wider range of platforms than 640x480.
