Add collection of grub configuration for UEFI systems

UEFI systems store the grub configuration at:

  /boot/efi/EFI/*/grub.conf [grub 1.x]
  /boot/efi/EFI/*/grub.cfg [grub 2.x]

Add these paths to the respective modules.

Signed-off-by: Bryn M. Reeves <bmr@redhat.com>