[source] xtables-addons: fix build error on ARC

[LEDE Commits]

nbd pushed a commit to source.git, branch master:
https://git.lede-project.org/055e9dfb580c3d5f36a98dd9c27ff284288676a6

commit 055e9dfb580c3d5f36a98dd9c27ff284288676a6
Author: Felix Fietkau <nbd at nbd.name>
AuthorDate: Tue Mar 7 09:18:18 2017 +0100

    xtables-addons: fix build error on ARC
    
    The kernel unconditionally pulls in a header file that defines
    'current', which conflicts with the lua extension code.
    
    Signed-off-by: Felix Fietkau <nbd at nbd.name>
---
 .../xtables-addons/patches/201-fix-lua-packetscript.patch     | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/package/network/utils/xtables-addons/patches/201-fix-lua-packetscript.patch b/package/network/utils/xtables-addons/patches/201-fix-lua-packetscript.patch
index 02250ec..7599684 100644
--- a/package/network/utils/xtables-addons/patches/201-fix-lua-packetscript.patch
+++ b/package/network/utils/xtables-addons/patches/201-fix-lua-packetscript.patch
@@ -105,3 +105,14 @@
  #endif
  
  #if defined(__cplusplus)
+--- a/extensions/LUA/lua/llex.h
++++ b/extensions/LUA/lua/llex.h
+@@ -10,6 +10,8 @@
+ #include "lobject.h"
+ #include "lzio.h"
+ 
++/* prevent conflict with definition from asm/current.h */
++#undef current
+ 
+ #define FIRST_RESERVED	257
+