can: mcp251xfd: mcp251xfd_register(): prepare to activate PLL after softreset

If the PLL is needed it must be switched on after chip reset. This
patch adds the required call to mcp251xfd_register().

Link: https://lore.kernel.org/all/20220207131047.282110-15-mkl@pengutronix.deSigned-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c

@@ -1792,6 +1792,12 @@ static int mcp251xfd_register(struct mcp251xfd_priv *priv)
 	if (err)
 		goto out_chip_sleep;
 
+	err = mcp251xfd_chip_clock_init(priv);
+	if (err == -ENODEV)
+		goto out_runtime_disable;
+	if (err)
+		goto out_chip_sleep;
+
 	err = mcp251xfd_register_chip_detect(priv);
 	if (err)
 		goto out_chip_sleep;