Avoid the need for a custom header file for ESP32 compilation.

[tschundler]

Can be reverted when espressif/esp-idf#5429 is resolved.

[runger1101001]

I like it. It will make everyone's life easier who is trying to use ESP32. At the same time, it will be backward compatible with anyone who has already modified the header.
If we merge it, we should remove that part of the ESP32 docs. @askuric what do you think? @byDagor ?

[askuric]

Hey guys, I'll test it in the next few days
I've actually tried this on the beginning and it did not work.
You still needed the header file changes in order for the cast to work.

Let me look into it and if it works well be glad to merge it :)

[askuric]

Hey @tschundler and @runger1101001,

I've just tested the code and it works great!
No more need to update the mcpwm.h file 🥳 💪

Thanks a lot, I'm merging and I'll update the docs in the next iteration!