ASoC: Intel: atom: Remove unused functions

ASoC: Intel: atom: Remove unused functions

sst_cdev_fragment_elapsed() was added in 2014 by
commit 7adab122a57c ("ASoC: Intel: sst - add compressed ops handling")
but has remained unused.

sst_get_stream_allocated() was added in 2014 by
commit cc547054d312 ("ASoC: Intel: sst - add pcm ops handling")
but has remained unused.

sst_wait_interruptible() was added in 2014 by
commit 60dc8dbacb00 ("ASoC: Intel: sst: Add some helper functions")
but has remained unused.

Remove them.

Signed-off-by: "Dr. David Alan Gilbert" <linux@treblig.org>
Link: https://patch.msgid.link/20250509003716.278416-1-linux@treblig.org
Signed-off-by: Mark Brown <broonie@kernel.org>