Add static hashCheck variable to LwDecoDrgSN50v3L class (#25031)

Added a static variable 'hashCheck' to the LwDecoDrgSN50v3L class.

tasmota/berry/lorawan/decoders/vendors/dragino/SN50v3L.be

@@ -11,6 +11,8 @@ if !global.DrgSN50v3LNodes      # data survive to decoder reload
 end
 
 class LwDecoDrgSN50v3L
+  static var hashCheck = false
+
   static def decodeUplink(Name, Node, RSSI, FPort, Bytes)
     var data = {"Device":"Dragino SN50v3-L"}