Do not wait the full time when no gsm signal can be found

GpsTracker/Network.cpp

@@ -12,6 +12,7 @@ namespace network {
 
 	SIM808RegistrationStatus waitForRegistered(uint32_t timeout) {
 		SIM808RegistrationStatus currentStatus;
+		uint8_t noNetwork = 0;
 
 		do {
 			currentStatus = hardware::sim808::device.getNetworkRegistrationStatus();
@@ -19,6 +20,14 @@ namespace network {
 
 			SIM808SignalQualityReport report = hardware::sim808::device.getSignalQuality();
 			VERBOSE_FORMAT("waitForRegistered", "%d, [%d %ddBm]", currentStatus.stat, report.ssri, report.attenuation);
+			
+			if (report.ssri == 0) noNetwork++;
+			else noNetwork = 0;
+			if (noNetwork > 3) {
+				VERBOSE_MSG("waitForRegistered", "No signal");
+				break; //after a while, not network really means no network. Bailing out
+			}
+
 			mainunit::deepSleep(NETWORK_DEFAULT_INTERMEDIATE_TIMEOUT_MS / 1000);
 			timeout -= NETWORK_DEFAULT_INTERMEDIATE_TIMEOUT_MS;
 		} while (timeout > 1);