irqchip/wpcm450: Fix memory leak in wpcm450_aic_of_init()

If of_iomap() failed, 'aic' should be freed before return. Otherwise
there is a memory leak.

Fixes: fead4dd49663 ("irqchip: Add driver for WPCM450 interrupt controller")
Signed-off-by: Wei Yongjun <[e-mail]>
Reviewed-by: Jonathan Neuschäfer <[e-mail]>
Signed-off-by: Marc Zyngier <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

drivers/irqchip/irq-wpcm450-aic.c

···
 	aic->regs = of_iomap(node, 0);
 	if (!aic->regs) {
 		pr_err("Failed to map WPCM450 AIC registers\n");
+		kfree(aic);
 		return -ENOMEM;
 	}