changes:
* EFI_GUID macro defined per your suggestion - efi_guid_t is now a struct of
char[16].  Fixed all GUID definitions.
* Made one unified efi_guid_unparse() static inline in asm-ia64/efi.h.
Removed three other definitions of similar in efivars.c and mca.c.
* fixed endianness of fs/partitions/efi.c - thanks to Richard Hirst and his
GPT work in Parted.
* cleaned up find_valid_gpt() to make it easier to see what's going on and
avoid future NULL ptr deref cases if this code gets modified yet again.
* Only use partition table slots 0..max_p.  The previous behaviour would let
you delete a partition in the middle of the table, and on next boot all the
partition numbers above that would switch down.  This change makes it
consistent with the MSDOS concept of primary partitions.  /dev/sdaX exists
iff the partition type is not NULL.
* Moved CONFIG_PARTITION_EFI help text to fs/partitions/Config.help