kernel: tune e1000e module parameters

kernel: tune e1000e module parameters

The default e1000e parameters (interrupt throttling rate, MSI/MSI-X
mode) are optimized for desktop and server computers to optimize
user-space execution (i.e. what's typically referred to as "useful"
work).  This assumption breaks on a router under load where most of
the "useful" work actually takes place either in hardware interrupt
handlers (IRQ) or at software IRQ (swirq) modes, so we try to reflect
that by overriding these parameters with more appropriate values.

Patch-by: Philip Prindeville <philipp@redfish-solutions.com>
Signed-off-by: Jo-Philipp Wich <jo@mein.io>