Add EFI-BOOT mount point

- optional
- depend on hokey "EFI System" GPT label, YMMV
- *TODO* use proper GPT UUID matching

builds/any/rootfs/jessie/common/overlay/etc/mtab.yml

@@ -17,3 +17,11 @@ mounts:
     mount: ro
     dir: /mnt/onl/boot
     fsck: false
+
+  # ESP (EFI system partition)
+  EFI-BOOT:
+    mount: ro
+    dir: /mnt/onl/efi-boot
+    fsck: false
+    label: EFI System
+    optional: true

packages/base/all/initrds/loader-initrd-files/src/etc/mtab.yml

@@ -18,3 +18,11 @@ mounts:
     mount: rw
     dir: /mnt/onl/boot
     fsck: true
+
+  # ESP (EFI system partition)
+  EFI-BOOT:
+    mount: ro
+    dir: /mnt/onl/efi-boot
+    fsck: false
+    label: EFI System
+    optional: true