qcacld-3.0: Remove nRssiFilterPeriod from struct hdd_config

Change I374e870610d79cc0d172ae126bfa70dc6d2db9a9 ("qcacld-3.0: Remove
not used INI CFG") removed support for the gRssiFilterPeriod
configuration item. However it failed to remove the underlying
nRssiFilterPeriod field from struct hdd_config, so do so now.

Change-Id: I5c8106e7ea57c7ab97213e17628caa1ecdd82b05
CRs-Fixed: 2367390

core/hdd/inc/wlan_hdd_cfg.h

@@ -2682,8 +2682,6 @@ struct hdd_config {
 	uint32_t nInitialDwellTime;     /* in units of milliseconds */
 	bool initial_scan_no_dfs_chnl;
 
-	uint8_t nRssiFilterPeriod;
-
 	uint8_t wow_data_inactivity_timeout;
 
 	uint32_t DelayedTriggerFrmInt;