[syslinux:master] Update gnu-efi submodule to 3.0.6

[syslinux-bot for Joakim Tjernlund]

Commit-ID:  446db7c2498b635703697ec84ebd5c51c4e9b452
Gitweb:     http://www.syslinux.org/commit/446db7c2498b635703697ec84ebd5c51c4e9b452
Author:     Joakim Tjernlund <joakim.tjernlund at infinera.com>
AuthorDate: Thu, 9 Nov 2017 17:17:14 +0100
Committer:  Joakim Tjernlund <joakim.tjernlund at infinera.com>
CommitDate: Thu, 9 Nov 2017 19:03:50 +0100

Update gnu-efi submodule to 3.0.6


---
 gnu-efi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gnu-efi b/gnu-efi
index ab54e2b4..af5d1494 160000
--- a/gnu-efi
+++ b/gnu-efi
@@ -1 +1 @@
-Subproject commit ab54e2b40e914d0ca01dc3d44c8d4eb8517bf999
+Subproject commit af5d1494a91617c87521101f6f5979dfbd95903d