Hide speexdsp's echo cancellation implementation details behind an
EchoCanceller derived class. An AudioLayer may now instantiate
implementations of the EchoCanceller. This may be platform specific
compile-time or swapped out at runtime.
Introduces a null echo canceller for testing. As the speexdsp aec
is not currently functional, the null echo canceller is replaced
as the default implementation.
GitLab: #454
Change-Id: I169f1e9758afbed884fc42d9d78a69ce28d12fe2
fix preferences set in first plugin loading
small logic changes in libraries loading
related to: https://review.jami.net/c/ring-project/+/14433
Change-Id: I4730f279ee38d337e3ef94dd9562a5dfc1a63c32
