bcma: mips: fix clearing device IRQ

We were using wrong IRQ number so clearing wasn't working at all.
Depending on a platform this could result in a one device having two
interrupts assigned. On BCM4706 this resulted in all IRQs being broken.

Cc: Hauke Mehrtens <hauke@hauke-m.de>
Cc: stable@vger.kernel.org
Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Acked-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/bcma/driver_mips.c b/drivers/bcma/driver_mips.c
index c45ded8..792daad 100644
--- a/drivers/bcma/driver_mips.c
+++ b/drivers/bcma/driver_mips.c
@@ -115,7 +115,7 @@
 			    bcma_read32(mdev, BCMA_MIPS_MIPS74K_INTMASK(0)) &
 			    ~(1 << irqflag));
 	else
-		bcma_write32(mdev, BCMA_MIPS_MIPS74K_INTMASK(irq), 0);
+		bcma_write32(mdev, BCMA_MIPS_MIPS74K_INTMASK(oldirq), 0);
 
 	/* assign the new one */
 	if (irq == 0) {