More improvements to auto GPS screen readout

Read fix quality and type changes.
Read satellite count changes.
Reduced minimum time between readouts to 8 seconds.
say km/h instead of kmh  for speed.

openrtx/src/core/voicePromptUtils.c

@@ -649,7 +649,8 @@ void vp_announceGPSInfo(vpGPSInfoFlags_t gpsInfoFlags)
         // speed/altitude:
         snprintf(buffer, 16, "%4.1fkm/h", state.gps_data.speed);
         vp_queuePrompt(PROMPT_SPEED);
-        vp_queueString(buffer, vpAnnounceCommonSymbols);
+        vp_queueString(buffer, 
+                       vpAnnounceCommonSymbols|vpAnnounceLessCommonSymbols);
     }
     
     if (gpsInfoFlags & vpGPSAltitude)

openrtx/src/ui/ui.c

@@ -1137,17 +1137,18 @@ void ui_saveState()
 static float priorGPSSpeed = 0;
 static float priorGPSAltitude = 0;
 static float  priorGPSDirection = 500; // impossible value init.
+static uint8_t priorGPSFixQuality= 0;
+static uint8_t priorGPSFixType = 0;
+static uint8_t    priorSatellitesInView = 0;
 static uint32_t vpGPSLastUpdate = 0;
 
 static vpGPSInfoFlags_t GetGPSDirectionOrSpeedChanged()
 {
     if (!state.settings.gps_enabled) 
         return vpGPSNone;
-    if (state.gps_data.fix_quality == 0 || state.gps_data.fix_quality >= 6)
-        return vpGPSNone;
     
     uint32_t now = getTick();
-    if (now - vpGPSLastUpdate < 10000)
+    if (now - vpGPSLastUpdate < 8000)
         return vpGPSNone;
     
     vpGPSInfoFlags_t whatChanged=  vpGPSNone;
@@ -1185,6 +1186,12 @@ static vpGPSInfoFlags_t GetGPSDirectionOrSpeedChanged()
         priorGPSDirection = state.gps_data.tmg_true;
     }
     
+    if (state.gps_data.satellites_in_view != priorSatellitesInView)
+    {
+        whatChanged |= vpGPSSatCount;
+        priorSatellitesInView = state.gps_data.satellites_in_view;
+    }
+    
     if (whatChanged)
         vpGPSLastUpdate=now;