ENH: turbulentDFSEMInlet: refactoring by PatchFunction1

- ENH: turbulentDFSEMInlet: add normalisation factors for
input Reynolds stresses, mean velocity and integral-length
scales as entries `Uref` and `Lref`.
- ENH: turbulentDFSEMInlet: add scaling factor entries, `scale`
and `m`, to enable users to tune C1 normalisation coefficient,
if need be.
- BUG: turbulentDFSEM: (fixes #1004 #1744 #2089)
- see #2090 for theoretical issues related to the DFSEM method.