i40e: use ktime_get_real_ts64 instead of ktime_to_timespec64

Remove a call to ktime_to_timespec64 by calling ktime_get_real_ts64
directly.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/i40e/i40e_ptp.c

@@ -725,7 +725,7 @@ static long i40e_ptp_create_clock(struct i40e_pf *pf)
 	pf->tstamp_config.tx_type = HWTSTAMP_TX_OFF;
 
 	/* Set the previous "reset" time to the current Kernel clock time */
-	pf->ptp_prev_hw_time = ktime_to_timespec64(ktime_get_real());
+	ktime_get_real_ts64(&pf->ptp_prev_hw_time);
 	pf->ptp_reset_start = ktime_get();
 
 	return 0;