[OE-core] [PATCH 1/1] grub-efi: Include GPT partition EXT FS support

[Darren Hart]

Fixes [YOCTO 2257]

GPT partitions are common for EFI systems. Add support for them by
including the part_gpt partition module in the grub-efi image. In
order to allow for loading a Linux kernel from an EXT* filesystem,
include the ext2 module as well.

With this fix applied, I was able to boot from a USB key using a
GPT partition table with the following layout:

  $ sudo gdisk -l /dev/sdc
  GPT fdisk (gdisk) version 0.8.2

  Partition table scan:
    MBR: protective
    BSD: not present
    APM: not present
    GPT: present

  Found valid GPT with protective MBR; using GPT.
  Disk /dev/sdc: 7669824 sectors, 3.7 GiB
  Logical sector size: 512 bytes
  Disk identifier (GUID): 68FA7CD4-E0C3-4A8E-82B5-1331C9B17A3C
  Partition table holds up to 128 entries
  First usable sector is 34, last usable sector is 7669790
  Partitions will be aligned on 2-sector boundaries
  Total free space is 7428816 sectors (3.5 GiB)

  Number  Start (sector)    End (sector)  Size       Code  Name
     1              34           32801   16.0 MiB    0700      # FAT16
     2           32802          240974   101.6 MiB   0700      # EXT3