qcacmn: Add fixes in snapshot read logic

1. Initialize the temporary variable to read snapshot to zero.
2. Read correct number of shared snapshot values.

CRs-Fixed: 3026029
Change-Id: I6f4fc9d1d2bfe4818304be16f7c80830b4fb260b

target_if/mgmt_txrx/src/target_if_mgmt_txrx_rx_reo.c

@@ -181,6 +181,8 @@ target_if_mgmt_rx_reo_read_snapshot(
 		return QDF_STATUS_E_INVAL;
 	}
 
+	qdf_mem_zero(snapshot_value, sizeof(*snapshot_value));
+
 	low_level_ops = target_if_get_mgmt_rx_reo_low_level_ops(
 				wlan_pdev_get_psoc(pdev));