Change .ptt_type to RIG_PTT_RIG for RIG_MODEL_DUMMY

With the old value of RIG_PTT_NONE, dummy_get_ptt() and dummy_set_ptt()
were never called because rig_get_ptt() and rig_set_ptt() do check
.ptt_type and return -RIG_ENAVAIL in that case.

Do not change .ptt_type for RIG_MODEL_DUMMY_NOVFO so that both cases
can be tested if needed.

rigs/dummy/dummy.c

@@ -2460,7 +2460,7 @@ struct rig_caps dummy_caps =
     .status =         RIG_STATUS_STABLE,
     .rig_type =       RIG_TYPE_OTHER,
     .targetable_vfo = RIG_TARGETABLE_PTT | RIG_TARGETABLE_RITXIT | RIG_TARGETABLE_FREQ | RIG_TARGETABLE_MODE | RIG_TARGETABLE_SPECTRUM,
-    .ptt_type =       RIG_PTT_NONE,
+    .ptt_type =       RIG_PTT_RIG,
     .dcd_type =       RIG_DCD_RIG,
     .port_type =      RIG_PORT_NONE,
     .has_get_func =   DUMMY_FUNC,