Fix RFPOWER command for TS480

https://github.com/Hamlib/Hamlib/issues/553

rigs/kenwood/kenwood.c

@@ -2339,7 +2339,7 @@ static int kenwood_get_power_minmax(RIG *rig, int *power_now, int *power_min,
         RETURNFUNC( -RIG_EPROTO);
     }
 
-    if (RIG_IS_TS890S)
+    if (RIG_IS_TS890S || RIG_IS_TS480)
     {
         n = sscanf(levelbuf, "PC%d;", power_now);
 

rigs/kenwood/kenwood.h

@@ -27,7 +27,7 @@
 #include <string.h>
 #include "token.h"
 
-#define BACKEND_VER "20210209"
+#define BACKEND_VER "20210221"
 
 #define EOM_KEN ';'
 #define EOM_TH '\r'