RFR: JDK-8055784,Not Excluding Unimplemented Devices from DIO Build When STRIP_PACKAGES is defined

[Jen Dority]

issue: https://bugs.openjdk.java.net/browse/JDK-8055784
webrev: http://cr.openjdk.java.net/~jld/8055784/

Hi All,

Need a small review for this change which fixes some selective 
compilation issues with the Device I/O projects.

1. Fixed the mechanism to exclude not yet implemented device APIs
2. Added GPIO to the list of excludable device APIs
3. Removed a couple of unnecessary dependencies between modules

Thanks,
Jen