libelf: make L1_MFN_VALID note known

We still don't use it (in the tool stack), and its values (plural) also
aren't fetched correctly, but it is odd to continue to see the
hypervisor log "ELF: note: unknown (0xd)" when loading a Linux Dom0.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Julien Grall <jgrall@amazon.com>

xen/common/libelf/libelf-dominfo.c

@@ -117,6 +117,7 @@ elf_errorstatus elf_xen_parse_note(struct elf_binary *elf,
         [XEN_ELFNOTE_FEATURES] = { "FEATURES", 1},
         [XEN_ELFNOTE_SUPPORTED_FEATURES] = { "SUPPORTED_FEATURES", 0},
         [XEN_ELFNOTE_BSD_SYMTAB] = { "BSD_SYMTAB", 1},
+        [XEN_ELFNOTE_L1_MFN_VALID] = { "L1_MFN_VALID", false },
         [XEN_ELFNOTE_SUSPEND_CANCEL] = { "SUSPEND_CANCEL", 0 },
         [XEN_ELFNOTE_MOD_START_PFN] = { "MOD_START_PFN", 0 },
         [XEN_ELFNOTE_PHYS32_ENTRY] = { "PHYS32_ENTRY", 0 },