Remove Device::from_raw() in favor of using Device::as_ref() + into().

[fbq]

First, there is an inconsistency between Device::from_raw() and ARef::from_raw() on whether the refcount gets increased or not. That means Device::from_raw() should be renamed. Moreover, as suggested here, Device::from_raw() can be avoid by using unsafe { Device::as_ref(ptr) }.into(). Things need to be done:

• Remove Device::from_raw().
• Add example usage in the documentation of Device::as_ref() and probably ARef as well

---

This requires submitting a proper patch to the LKML and the Rust for Linux mailing list. Please recall to test your changes, to use a proper title for the commit, to sign your commit under the Developer's Certificate of Origin and so on. Please see https://docs.kernel.org/process/submitting-patches.html and https://rust-for-linux.com/contributing for details.

Please take this issue only if you are new to the kernel development process and you would like to use it as a test to submit your first patch to the kernel. Please do not take it if you do not plan to make other contributions to the kernel.

[charmitro]

Perhaps @panosfol would like to take on this introductory patch for the kernel.

[panosfol]

Perhaps @panosfol would like to take on this introductory patch for the kernel.

Yes sounds good!