powerpc/powernv: Add a null pointer check in opal_event_init()

kasprintf() returns a pointer to dynamically allocated memory
which can be NULL upon failure.

Fixes: 2717a33 ("powerpc/opal-irqchip: Use interrupt names if present")
Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231127030755.1546750-1-chentao@kylinos.cn

Author: KunWuChan

arch/powerpc/platforms/powernv/opal-irqchip.c

@@ -275,6 +275,8 @@ int __init opal_event_init(void)
 		else
 			name = kasprintf(GFP_KERNEL, "opal");
 
+		if (!name)
+			continue;
 		/* Install interrupt handler */
 		rc = request_irq(r->start, opal_interrupt, r->flags & IRQD_TRIGGER_MASK,
 				 name, NULL);