Revert "Merge pull request #1121 from Zentyal/scabrero/dns-fix-error-booting"

This reverts commit 1c4f9483c43eb8c08b7ca28d229f699268a71ebd, reversing
changes made to 1b93cf2aeff0ee6e7b7fe0b1c6c13a5cc228843f.
Revert "Merge pull request #1102 from Zentyal/jacalvo/dns-gss-update"

This reverts commit d6c2f15794a440aa9e64567ed8a50e1628ee4c4b, reversing
changes made to 41d66cb38a6720b96b0050b12ff66d2271ebc39f.
Merge pull request #1155 from Zentyal/jacalvo/revert-dns-gss-update

Jacalvo/revert dns gss update