e1000e: resolve checkpatch JIFFIES_COMPARISON warning

WARNING:JIFFIES_COMPARISON: Comparing jiffies is almost always wrong;
prefer time_after, time_before and friends

Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>