Ensure SLS IDs are unique

Summary:
Commit ed2a64f0 introduced a new SLS ID rc, already assigned to another
state.

Fixes T1017.

Test Plan: Tested salt '*' state.highstate, it succeeded without error.

Reviewers: dereckson

Maniphest Tasks: T1017

Differential Revision: https://devcentral.nasqueron.org/D679