Fix remaining cppcheck redundant warnings

https://github.com/Hamlib/Hamlib/issues/1351

rigs/anytone/anytone.c

@@ -348,17 +348,11 @@ int anytone_get_vfo(RIG *rig, vfo_t *vfo)
 // ---------------------------------------------------------------------------
 int anytone_set_vfo(RIG *rig, vfo_t vfo)
 {
-    int retval = RIG_OK;
     //anytone_priv_data_t *p = rig->state.priv;
 
     ENTERFUNC;
     RETURNFUNC(RIG_OK);
 
-    if (rig == NULL)
-    {
-        retval = -RIG_EARG;
-    }
-    RETURNFUNC(retval);
 }
 
 // ---------------------------------------------------------------------------

rigs/kenwood/th.c

@@ -1267,7 +1267,7 @@ th_get_level(RIG *rig, vfo_t vfo, setting_t level, value_t *val)
             return retval;
         }
 
-        if (ackbuf[4] < '0' || ackbuf[4] > '9')
+        if (ackbuf[4] < '0' || ackbuf[4] > '8')
         {
             return -RIG_EPROTO;
         }

rotators/ts7400/include/readADC.c

@@ -56,7 +56,7 @@ int read_calibration(int buf[NUM_CHANNELS][2])
                 buf[i][j] = cal[k];
                 k++;
 
-                if (k < NUM_CHANNELS * 2)
+                if (k < NUM_CHANNELS * 2 - 1)
                 {
                     printf(", ");
                 }

rotators/ts7400/include/test7400ADC.c

@@ -54,7 +54,7 @@ int read_calibration(int buf[NUM_CHANNELS][2])
                 buf[i][j] = cal[k];
                 k++;
 
-                if (k < NUM_CHANNELS * 2)
+                if (k < NUM_CHANNELS * 2 - 1)
                 {
                     printf(", ");
                 }