Add ETW.md documentation as Learning Path

[PrzemekWirkus]

We can use [ETW.md]arm-developer-tools/windowsperf/blob/main/ETW.md) documentation to prepare simple recipe for how to enable and use ETW with WindowsPerf wperf CLI.
PS: We can consider adding also recipe on how to use it with Kernel Driver.

Ad source of images, please use: https://gitlab.com/Linaro/WindowsPerf/windowsperf/-/merge_requests/671