efi_loader: Setup logical_partition media information

When adding a partition, set the logical_partition member in the media
structure as mandated by the UEFI spec.

Signed-off-by: Emmanuel Vadot <manu@freebsd.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

lib/efi_loader/efi_disk.c

@@ -258,6 +258,8 @@ static void efi_disk_add_dev(const char *name,
 	diskobj->media.block_size = desc->blksz;
 	diskobj->media.io_align = desc->blksz;
 	diskobj->media.last_block = desc->lba - offset;
+	if (part != 0)
+		diskobj->media.logical_partition = 1;
 	diskobj->ops.media = &diskobj->media;
 	return;
 out_of_memory: