Partial revert "e1000e: Avoid receiver overrun interrupt bursts"

This partially reverts commit 4aea7a5c.

We keep the fix for the first part of the problem (1) described in the log
of that commit, that is to read ICR in the other interrupt handler. We
remove the fix for the second part of the problem (2), Other interrupt
throttling.

Bursts of "Other" interrupts may once again occur during rxo (receive
overflow) traffic conditions. This is deemed acceptable in the interest of
avoiding unforeseen fallout from changes that are not strictly necessary.
As discussed, the e1000e driver should be in "maintenance mode".

Link: https://www.spinics.net/lists/netdev/msg480675.html


Signed-off-by: Benjamin Poirier <bpoirier@suse.com>
Acked-by: Alexander Duyck <alexander.h.duyck@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>