Add ksdk adc shim driver

[zephyrbot]

Reported by Maureen Helm:

Add ksdk adc shim driver

(Imported from Jira ZEP-1396)

[zephyrbot]

by Mark Linkmeyer:

Maureen Helm , in cleaning up issues in preparation of the move to GitHub issues, I cleared the FixVersion field for this story because it was set to 1.8 and 1.8 was already released. If you know when it is now planned to be released, please set the FixVersion field accordingly.