For tests we can pass a non related vring to just make it run, hence no
need of making it optional. Always pass the vring.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
The i2c crate now uses log crate to publish error, info and warn
messages, but doesn't initialize a logger yet and these messages never
make it out.
Initialize the env_logger to see these messages.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
The workspace section in Rust documentation suggests adding new crates
in the top level directory itself instead of the src folder. Remove the
top level src folder.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
