xtables-addons: fix various warning in lua patch

These will become errors in the next LTS kernel.

Signed-off-by: Rosen Penev <rosenp@gmail.com>
(cherry picked from commit 1cd93b673b)

net/xtables-addons/patches/200-add-lua-packetscript.patch

@@ -1137,7 +1137,7 @@
 +	struct xt_lua_tginfo *info = (void *)target->data;
 +
 +	info->state_id = 0;
-+	strncpy(info->function, "process_packet\0", sizeof("process_packet\0"));
++	strcpy(info->function, "process_packet\0");
 +}
 +
 +static int
@@ -5301,7 +5301,7 @@
 +      case OP_FORLOOP:
 +      case OP_FORPREP:
 +        checkreg(pt, a+3);
-+        /* go through */
++        fallthrough;
 +      case OP_JMP: {
 +        int dest = pc+1+b;
 +        /* not full check and jump is forward and do not skip `lastpc'? */
@@ -7716,6 +7716,7 @@
 +        }
 +        else if (sep == -1) return '[';
 +        else luaX_lexerror(ls, "invalid long string delimiter", TK_STRING);
++        fallthrough;
 +      }
 +      case '=': {
 +        next(ls);
@@ -7809,7 +7810,6 @@
 +  lua_assert(ls->lookahead.token == TK_EOS);
 +  ls->lookahead.token = llex(ls, &ls->lookahead.seminfo);
 +}
-+
 --- /dev/null
 +++ b/extensions/LUA/lua/llex.h
 @@ -0,0 +1,81 @@
@@ -12471,7 +12471,7 @@
 +      lua_number2int(k, n);
 +      if (luai_numeq(cast_num(k), nvalue(key))) /* index is int? */
 +        return luaH_getnum(t, k);  /* use specialized version */
-+      /* else go through */
++      fallthrough;
 +    }
 +    default: {
 +      Node *n = mainposition(t, key);
@@ -12766,7 +12766,7 @@
 +  if (!lua_isstring(L, -1))
 +    luaL_error(L, "invalid value (%s) at index %d in table for "
 +                  LUA_QL("concat"), luaL_typename(L, -1), i);
-+    luaL_addvalue(b);
++  luaL_addvalue(b);
 +}
 +
 +
@@ -17984,7 +17984,7 @@
 +	int32_t ret;
 +	struct lua_env * env = kmalloc(sizeof(struct lua_env), GFP_KERNEL);
 +
-+	if (!script_size > 0) {
++	if (!script_size) {
 +		pr_debug("LUA [%d]: script_size %lu < 0\n", state_id, script_size);
 +		return false;
 +	}