Let's kill i915_utils.h dependency.

Please notice that I used different wait strategies depending on each individual need. precision with ktime_t when needed, but simple wait counters when precision doesn't matter. some places with static wait cadence, and others (most) with increasing wait time for each failure. Then ones with a small wait at the end where I control with the wait vs the extra 'slept' var. and others with the huge wait at the last round. I'm opened to accept suggestions and change any or even all of them if someone has some good arguments ;)