Remove SNDDMA_GetSoundtime, because it was mostly copypasted from one
platform code to another.
SNDDMA_GetDMAPos gets removed too, as we have dma.samplepos for that.
The `.editorconfig` file in this repo is configured to trim all trailing
whitespace regardless of whether the line is modified.
Trims all trailing whitespace in the repository to make the codebase easier
to work with in editors that respect `.editorconfig`.
`git blame` becomes less useful on these lines but it already isn't very useful.
Commands:
```
find . -type f -name '*.h' -exec sed --in-place 's/[[:space:]]\+$//' {} \+
find . -type f -name '*.c' -exec sed --in-place 's/[[:space:]]\+$//' {} \+
```
Alibek Omarov