In the previous patch the function flexcan_write64() was introduced.
This patch replaces the open coded variant in flexcan_mailbox_read()
that marks a mailbox as read, by a single call to flexcan_write64().
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
        }
 
  mark_as_read:
-       if (priv->devtype_data->quirks & FLEXCAN_QUIRK_USE_OFF_TIMESTAMP) {
-               /* Clear IRQ */
-               if (n < 32)
-                       priv->write(BIT(n), ®s->iflag1);
-               else
-                       priv->write(BIT(n - 32), ®s->iflag2);
-       } else {
+       if (priv->devtype_data->quirks & FLEXCAN_QUIRK_USE_OFF_TIMESTAMP)
+               flexcan_write64(priv, FLEXCAN_IFLAG_MB(n), ®s->iflag1);
+       else
                priv->write(FLEXCAN_IFLAG_RX_FIFO_AVAILABLE, ®s->iflag1);
-       }
 
        /* Read the Free Running Timer. It is optional but recommended
         * to unlock Mailbox as soon as possible and make it available