Change rig_set_split_mode to disable/enable ptt by rig model as needed

https://github.com/Hamlib/Hamlib/issues/838

src/rig.c

@@ -4224,6 +4224,7 @@ int HAMLIB_API rig_set_split_mode(RIG *rig,
     const struct rig_caps *caps;
     int retcode, rc2;
     vfo_t curr_vfo, tx_vfo;
+    int split_fix = 0;
 
     ENTERFUNC;
 
@@ -4251,7 +4252,13 @@ int HAMLIB_API rig_set_split_mode(RIG *rig,
         RETURNFUNC(retcode);
     }
 
-    rig_set_split_vfo(rig,RIG_VFO_CURR, RIG_SPLIT_OFF, RIG_VFO_CURR);
+    // some rigs exhibit undesirable flashing when split is on
+    // and and we have to switch VFOS to set things
+    if (rig->caps->rig_model == RIG_MODEL_FT950)
+    {
+        rig_set_split_vfo(rig,RIG_VFO_CURR, RIG_SPLIT_OFF, RIG_VFO_CURR);
+        split_fix = 1;
+    }
     /* Assisted mode */
     curr_vfo = rig->state.current_vfo;
 
@@ -4323,7 +4330,10 @@ int HAMLIB_API rig_set_split_mode(RIG *rig,
         /* return the first error code */
         retcode = rc2;
     }
-    rig_set_split_vfo(rig,RIG_VFO_CURR, RIG_SPLIT_ON, RIG_VFO_CURR);
+    if (split_fix)
+    {
+        rig_set_split_vfo(rig,RIG_VFO_CURR, RIG_SPLIT_ON, RIG_VFO_CURR);
+    }
 
     RETURNFUNC(retcode);
 }