[MIPS] IP27: startup_bridge_irq: connect interrupt.

shutdown_bridge_irq disconnects the irq so we need to connect the irq or
requesting the same irq a send time will fail.  This used to make
things like ifconfig eth0 down; ifconfig eth0 up fail on IP27.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/sgi-ip27/ip27-irq.c b/arch/mips/sgi-ip27/ip27-irq.c
index 554a5c7..5cfbe1a 100644
--- a/arch/mips/sgi-ip27/ip27-irq.c
+++ b/arch/mips/sgi-ip27/ip27-irq.c
@@ -285,6 +285,8 @@
 
         bridge->b_wid_tflush;
 
+	intr_connect_level(cpu, swlevel);
+
         return 0;       /* Never anything pending.  */
 }