qcacld-3.0: Refactor six LFR INI cfg

Based on new cfg component, refactor below LFR INI cfg and remove
unused legacy codes.
 - CFG_ENABLE_LFR_SUBNET_DETECTION
 - CFG_ROAM_HO_DELAY_FOR_RX_NAME
 - CFG_MIN_DELAY_BTW_ROAM_SCAN_NAME
 - CFG_ROAM_SCAN_TRIGGER_REASON_BITMASK_NAME
 - CFG_ROAM_FT_OPEN_ENABLE_NAME
 - CFG_ROAM_FORCE_RSSI_TRIGGER_NAME

Change-Id: Iaa738c6416dffe8159b49d59fc9a514da2fbb7ff
CRs-Fixed: 2376637

mlme/dispatcher/inc/wlan_mlme_ucfg_api.h

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018 The Linux Foundation. All rights reserved.
+ * Copyright (c) 2018-2019 The Linux Foundation. All rights reserved.
  *
  * Permission to use, copy, modify, and/or distribute this software for
  * any purpose with or without fee is hereby granted, provided that the
@@ -3482,4 +3482,26 @@ QDF_STATUS
 ucfg_mlme_get_scan_11d_interval(struct wlan_objmgr_psoc *psoc,
 				uint32_t *value);
 
+#ifdef FEATURE_LFR_SUBNET_DETECTION
+/**
+ * ucfg_mlme_is_subnet_detection_enabled() - check if sub net detection is
+ * enabled/disabled
+ * @psoc: pointer to psoc object
+ * @value: value that is requested by the caller
+ *
+ * Inline UCFG API to be used by HDD/OSIF callers
+ *
+ * Return: QDF_STATUS_SUCCESS - in case of success
+ */
+QDF_STATUS
+ucfg_mlme_is_subnet_detection_enabled(struct wlan_objmgr_psoc *psoc, bool *val);
+#else
+static QDF_STATUS
+ucfg_mlme_is_subnet_detection_enabled(struct wlan_objmgr_psoc *psoc, bool *val)
+{
+	*val = false;
+
+	return QDF_STATUS_SUCCESS;
+}
+#endif /* FEATURE_LFR_SUBNET_DETECTION */
 #endif /* _WLAN_MLME_UCFG_API_H_ */