Remove deprecated profiling config parameters, clarify docs

We've already broken profiling completely in this release. Make
this abundantly clear in the RELEASE-NOTES and just remove the
awful back-compat attempt from I2af28cd3 and I49c0a83e.

Change-Id: Ib0b87192e2a6e87db19f7821906dd7b2063081e3
Merge "Remove deprecated profiling config parameters, clarify docs"