unused vararg suppression, re-enable unused args luacheck

scada-common/util.lua

@@ -117,6 +117,7 @@ function util.strwrap(str, limit) return cc_strings.wrap(str, limit) end
 ---@nodiscard
 ---@vararg any
 ---@return string
+---@diagnostic disable-next-line: unused-vararg
 function util.concat(...)
     local str = ""
     for _, v in ipairs(arg) do str = str .. util.strval(v) end
@@ -130,6 +131,7 @@ util.c = util.concat
 ---@nodiscard
 ---@param format string
 ---@vararg any
+---@diagnostic disable-next-line: unused-vararg
 function util.sprintf(format, ...)
     return string.format(format, table.unpack(arg))
 end