Make DOH more friendly to other AMD loaders:
    - specify baseUrl explicitly
    - specify mapping from doh --> util/doh explicitly
    - don't depend on mapping from doh to doh/main
    Make DOH more friendly to other AMD loaders (continuation):
    use tlmSiblingOfDojo etc. to make things still work with dojo V1 loader

    Refs #16585
Revert "Make DOH more friendly to other AMD loaders (continuation)"

This reverts commit 0bd911d395e08c929f5b252a2fec18d688fb27b6.
Use requirejs rather than dojo.js.
Avoids hang with the double-indirection where _parseUrlArgs script-injects dojo.js,
and then dojo.js script-injects require.js.