Missed icom.h commit

https://github.com/Hamlib/Hamlib/issues/448

(cherry picked from commit 0fa00cb14f)

rigs/icom/icom.h

@@ -203,6 +203,7 @@ struct icom_priv_data
     int x25cmdfails;  // This will get set if the 0x25 command fails so we try just once
     int x1cx03cmdfails;  // This will get set if the 0x1c 0x03 command fails so we try just once
     int poweron;  // to prevent powering on more than once
+    int filter;   // Current filter selected 
 };
 
 extern const struct ts_sc_list r8500_ts_sc_list[];