MIPS: OCTEON: irq: Fix potential NULL pointer dereference

There is a potential NULL pointer dereference in case kzalloc()
fails and returns NULL.

Fix this by adding a NULL check on *cd*

This bug was detected with the help of Coccinelle.

Fixes: 64b139f97c01 ("MIPS: OCTEON: irq: add CIB and other fixes")
Cc: [e-mail]
Signed-off-by: Gustavo A. R. Silva <[e-mail]>
Signed-off-by: Thomas Bogendoerfer <[e-mail]>

arch/mips/cavium-octeon/octeon-irq.c

···
 	}
 
 	cd = kzalloc(sizeof(*cd), GFP_KERNEL);
+	if (!cd)
+		return -ENOMEM;
+
 	cd->host_data = host_data;
 	cd->bit = hw;