Add debug for DHCP check

package/src/client2server-unified.lua

@@ -493,7 +493,9 @@ local function co_dhcp()
     local leases = {}
     
     while true do
+        if cfg.debug then log("debug", "CHECK DHCP") end
         local f = io.open("/var/lib/dnsmasq/dnsmasq.leases", "r")
+        if not f and cfg.debug then log("debug", "No DHCP file") end
         if f then
             local current = {}
             for line in f:lines() do