Don't removeAll current firmware directory

[ofaurax]

When running the flasher on a local file, its whole dir is emptied by RemoveAll.

This is to ensure cleanup of firmware download dir, but will also remove all files beside the firmware on local test.
We should handle this at another level.

This PR removes the RemoveAll on non-tmp directories, to be safe.

[DoctorVin]

Does Flasher actually create a temporary directory? I'm concerned that if Flasher no longer cleans up, we may accumulate junk where we don't expect it.

[ofaurax]

@DoctorVin we won't accumulate junk, because the functions that are downloading the data are cleaning the created (temporary) dir.

We have functions that download stuff in a temporary dir, then clean it, and we have functions that upload files and also clean the dir in which there is the uploaded file. Only downloaded stuff should be cleaned IMO.