Define
* GRUB_EFI_PERSISTENT_MEMORY (UEFI memory map type 14) per UEFI 2.5
* GRUB_MEMORY_PERSISTENT (E820 type 7) per ACPI 3.0
* GRUB_MEMORY_PERSISTENT_LEGACY (E820 unofficial type 12) per ACPI 3.0

and translate GRUB_EFI_PERSISTENT_MEMORY to GRUB_MEMORY_PERSISTENT in
grub_efi_mmap_iterate().

Includes
* adding the E820 names to lsmmap
* handling the E820 types in make_efi_memtype()
Suggested-by: Vladimir 'φ-coder/phcoder' Serbinenko <phcoder@gmail.com>
Suggested-by: Andrei Borzenkov <arvidjaar@gmail.com>