We have been building Cloud Hypervisor with command like:
`cargo build --no-default-features --features ...`.
After implementing ACPI, we donot have to use specify all features
explicitly. Default build command `cargo build` can work.
This commit fixed some build warnings with default build option and
changed github workflow correspondingly.
Signed-off-by: Michael Zhao <michael.zhao@arm.com>
This has been lagging behind on an older Rust version and we have
enough coverage from our Jenkins CI agent.
Signed-off-by: Rob Bradford <robert.bradford@intel.com>