e1000e: clearing interrupt timers causes descriptors to get flushed

Clearing the interrupt timers following an IMS clear has the unwanted
side-effect of flushing all descriptors immediately following a partial
write when interrupts are disabled.
Signed-off-by: NBruce Allan <bruce.w.allan@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/e1000e/netdev.c

@@ -2441,8 +2441,6 @@ static void e1000_configure_rx(struct e1000_adapter *adapter)
 		ew32(ITR, 1000000000 / (adapter->itr * 256));
 
 	ctrl_ext = er32(CTRL_EXT);
-	/* Reset delay timers after every interrupt */
-	ctrl_ext |= E1000_CTRL_EXT_INT_TIMER_CLR;
 	/* Auto-Mask interrupts upon ICR access */
 	ctrl_ext |= E1000_CTRL_EXT_IAME;
 	ew32(IAM, 0xffffffff);