usb: typec: fusb302: Make fusb302_irq_work static

Fix sparse warning:

drivers/usb/typec/tcpm/fusb302.c:1454:6: warning:
symbol 'fusb302_irq_work' was not declared. Should it be static?

Signed-off-by: YueHaibing <[e-mail]>
Reviewed-by: Guenter Roeck <[e-mail]>
Reviewed-by: Heikki Krogerus <[e-mail]>
Reviewed-by: Mukesh Ojha <[e-mail]>
Signed-off-by: Greg Kroah-Hartman <[e-mail]>

drivers/usb/typec/tcpm/fusb302.c

···
 	return IRQ_HANDLED;
 }
 
-void fusb302_irq_work(struct work_struct *work)
+static void fusb302_irq_work(struct work_struct *work)
 {
 	struct fusb302_chip *chip = container_of(work, struct fusb302_chip,
 						 irq_work);