DCM features should gate on OS and feature name

[qDot]

Currently, DCMs are gated only by feature. However, they should gate with a combination of feature and target_os, which means we can use default feature sets for all platforms, ignore DCMs that won't build for certain platforms (i.e. no serial on android) and only retract DCM features if someone is using no_default_features.

[qDot]

Fixed in 6.2.2