lxc: bump to 2.1.0

Bump LXC package from 1.1.5 to 2.1.0. Version 2.x includes many
improvements and optimizations.

https://linuxcontainers.org/lxc/news/

Some tools like lxc-top are rewritten in C and are no longer broken and
dependent on lua.

Signed-off-by: Marko Ratkaj <marko.ratkaj@sartura.hr>

utils/lxc/patches/002-compile.patch

@@ -0,0 +1,10 @@
+--- a/src/lxc/storage/aufs.h
++++ b/src/lxc/storage/aufs.h
+@@ -24,7 +24,6 @@
+ #ifndef __LXC_AUFS_H
+ #define __LXC_AUFS_H
+ 
+-#define _GNU_SOURCE
+ #include <stdbool.h>
+ #include <stdio.h>
+ #include <stdint.h>