applications: serial_lte_modem: Add GNSS data to carrier library

When carrier library is enabled the GNSS data will be provided using
the lwm2m_carrier_location_set() and lwm2m_carrier_velocity_set() API.

applications/serial_lte_modem/src/gnss/slm_at_gnss.c

@@ -27,6 +27,11 @@ static void pgps_event_handler(struct nrf_cloud_pgps_event *event);
 
 #endif /* CONFIG_SLM_NRF_CLOUD */
 
+#if defined(CONFIG_SLM_CARRIER)
+#include <time.h>
+#include <lwm2m_carrier.h>
+#endif
+
 #include "slm_util.h"
 #include "slm_at_host.h"
 #include "slm_at_gnss.h"
@@ -517,14 +522,7 @@ static void fix_rep_wk(struct k_work *work)
 		}
 	}
 
-#if defined(CONFIG_SLM_NRF_CLOUD)
-
-	if (slm_nrf_cloud_send_location && slm_nrf_cloud_ready) {
-		/* Report to nRF Cloud by best-effort */
-		send_location(&pvt);
-	}
-
-#if defined(CONFIG_NRF_CLOUD_PGPS) && defined(CONFIG_SLM_PGPS_INJECT_FIX_DATA)
+#if defined(CONFIG_SLM_PGPS_INJECT_FIX_DATA) || defined(CONFIG_SLM_CARRIER)
 	struct tm gps_time = {
 		.tm_year = pvt.datetime.year - 1900,
 		.tm_mon  = pvt.datetime.month - 1,
@@ -533,14 +531,36 @@ static void fix_rep_wk(struct k_work *work)
 		.tm_min  = pvt.datetime.minute,
 		.tm_sec  = pvt.datetime.seconds,
 	};
+#endif
+
+#if defined(CONFIG_SLM_NRF_CLOUD)
+
+	if (slm_nrf_cloud_send_location && slm_nrf_cloud_ready) {
+		/* Report to nRF Cloud by best-effort */
+		send_location(&pvt);
+	}
 
+#if defined(CONFIG_NRF_CLOUD_PGPS) && defined(CONFIG_SLM_PGPS_INJECT_FIX_DATA)
 	/* help date_time to save SNTP transactions */
 	date_time_set(&gps_time);
 	/* help nrf_cloud_pgps as most recent known location */
 	nrf_cloud_pgps_set_location(pvt.latitude, pvt.longitude);
 #endif
 
 #endif /* CONFIG_SLM_NRF_CLOUD */
+
+#if defined(CONFIG_SLM_CARRIER)
+	lwm2m_carrier_location_set(pvt.latitude,
+				   pvt.longitude,
+				   pvt.altitude,
+				   (uint32_t)mktime(&gps_time),
+				   pvt.accuracy);
+	lwm2m_carrier_velocity_set(pvt.heading,
+				   pvt.speed,
+				   pvt.vertical_speed,
+				   pvt.speed_accuracy,
+				   pvt.vertical_speed_accuracy);
+#endif /* CONFIG_SLM_CARRIER */
 }
 
 static void on_gnss_evt_fix(void)