irqchip/irq-imx-gpcv2: Fix spinlock initialization

The raw_spinlock in the IMX GPCV2 interupt chip is not initialized before
usage. That results in a lockdep splat:

  INFO: trying to register non-static key.
  the code is fine but needs lockdep annotation.
  turning off the locking correctness validator.

Add the missing raw_spin_lock_init() to the setup code.

Fixes: e324c4dc4a ("irqchip/imx-gpcv2: IMX GPCv2 driver for wakeup sources")
Signed-off-by: Tyler Baker <tyler.baker@linaro.org>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Cc: jason@lakedaemon.net
Cc: marc.zyngier@arm.com
Cc: shawnguo@kernel.org
Cc: andrew.smirnov@gmail.com
Cc: linux-arm-kernel@lists.infradead.org
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20170413222731.5917-1-tyler.baker@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

drivers/irqchip/irq-imx-gpcv2.c

@@ -230,6 +230,8 @@ static int __init imx_gpcv2_irqchip_init(struct device_node *node,
 		return -ENOMEM;
 	}
 
+	raw_spin_lock_init(&cd->rlock);
+
 	cd->gpc_base = of_iomap(node, 0);
 	if (!cd->gpc_base) {
 		pr_err("fsl-gpcv2: unable to map gpc registers\n");