EDAC, thunderx: Fix memory leak in thunderx_l2c_threaded_isr()

Fix memory leak in L2c threaded interrupt handler.

 [ bp: Rewrite commit message. ]

Fixes: 4100339 ("EDAC, thunderx: Add Cavium ThunderX EDAC driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
CC: David Daney <david.daney@cavium.com>
CC: Jan Glauber <jglauber@cavium.com>
CC: Mauro Carvalho Chehab <mchehab@kernel.org>
CC: Sergey Temerkhanov <s.temerkhanov@gmail.com>
CC: linux-edac <linux-edac@vger.kernel.org>
Link: http://lkml.kernel.org/r/20181013102843.GG16086@mwanda

drivers/edac/thunderx_edac.c

@@ -1884,7 +1884,7 @@ static irqreturn_t thunderx_l2c_threaded_isr(int irq, void *irq_id)
 	default:
 		dev_err(&l2c->pdev->dev, "Unsupported device: %04x\n",
 			l2c->pdev->device);
-		return IRQ_NONE;
+		goto err_free;
 	}
 
 	while (CIRC_CNT(l2c->ring_head, l2c->ring_tail,
@@ -1906,7 +1906,7 @@ static irqreturn_t thunderx_l2c_threaded_isr(int irq, void *irq_id)
 		l2c->ring_tail++;
 	}
 
-	return IRQ_HANDLED;
+	ret = IRQ_HANDLED;
 
 err_free:
 	kfree(other);