Name deploy-ironic and deploy-baremetal files uniq

Updates the 51-install-tgt and 52-install-busybox files
in both the deploy-ironic and deploy-baremetal elements
so that they have unique names.

While an end user would never use these elements at the same time we
should always use unique names for things per DIB conventions.

Change-Id: I8926870e45849341c10b2d479ddee45f9b625e2b
Add test to ensure we don't duplicate filenames

Add a new test_no_dup_filenames module to help ensure we don't have
duplicate names across elements.

Change-Id: I2af4a614f71fe58eba04e3fc50d3c0a70dd91f71
Merge "Name deploy-ironic and deploy-baremetal files uniq"
Merge "Add test to ensure we don't duplicate filenames"