e1000e: Add e1000e trace module

Add tracepoints to the driver via a new file e1000e_trace.h and some new
trace calls added in interesting places in the driver. Add some tracing
for s0ix flows to help in a debug of shared resources with the CSME
firmware. The idea here is that tracepoints have such low performance cost
when disabled that we can leave these in the upstream driver.

Performance not affected, and this can be very useful for debugging and
adding new trace events to paths in the future.

Usage:
echo "e1000e_trace:*" > /sys/kernel/debug/tracing/set_event
echo 1 > /sys/kernel/debug/tracing/events/e1000e_trace/enable

Signed-off-by: Sasha Neftin <sasha.neftin@intel.com>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>