Add support for no_std
Add features for building for std and no_std environments. A no-std
feature is explicitly added to enable the required math support.
Replaces the no_std branch.
Add a no_std
target (Cortex-M0) to CI to ensure it continues to build.
Additionally, made sure it builds for UEFI target.
cargo +nightly build --no-default-features --features=no-std \
--target x86_64-unknown-uefi -Z build-std=core,alloc
Edited by Tim Crawford