extcon: extcon-pd-virtual: add vpd->irq_lock initialisation

This fixes the follwing error.
  [   22.309582] BUG: spinlock bad magic on CPU#4, irq/107-virtual/297
  [   22.309618]  lock: 0xffff0000071cb2b8, .magic: 00000000, .owner: <none>/-1, .owner_cpu: 0
  [   22.309633] CPU: 4 PID: 297 Comm: irq/107-virtual Not tainted 5.10.110-52-rockchip ayufan-rock64#52
  [   22.309636] Hardware name: Radxa ROCK 4C+ (DT)
  [   22.309641] Call trace:
  [   22.309652]  dump_backtrace+0x0/0x1b4
  [   22.309656]  show_stack+0x24/0x30
  [   22.309663]  dump_stack_lvl+0xc8/0xf8
  [   22.309667]  dump_stack+0x18/0x34
  [   22.309674]  spin_bug+0x90/0xb4
  [   22.309678]  do_raw_spin_lock+0x44/0xe0
  [   22.309684]  _raw_spin_lock_irqsave+0x30/0x44
  [   22.309700]  vpd_irq_disable+0x30/0x80 [extcon_pd_virtual]
  [   22.309706]  dp_det_irq_handler+0x4c/0x60 [extcon_pd_virtual]
  [   22.309714]  irq_thread_fn+0x38/0x80
  [   22.309717]  irq_thread+0xec/0x198
  [   22.309723]  kthread+0xf8/0x108
  [   22.309728]  ret_from_fork+0x10/0x30

Signed-off-by: Stephen <stephen@radxa.com>

Author: RadxaStephen

drivers/extcon/extcon-pd-virtual.c

@@ -342,6 +342,7 @@ static int vpd_extcon_probe(struct platform_device *pdev)
 	}
 
 	vpd_extcon_init(vpd);
+	spin_lock_init(&vpd->irq_lock);
 	INIT_DELAYED_WORK(&vpd->irq_work, extcon_pd_delay_irq_work);
 
 	vpd->irq=gpiod_to_irq(vpd->gpio_irq);