Refactor PCE network analyzer PceOtnNode step 5

Refactor PCE network analyzer PceOtnNode step 5

There is no point to have a different treatment for SERVICE_TYPE_100GE_S
in initXndrTps() to determine the attribute 'valid'.
This specific treatment only affects the argument availableXpdrClientTps
to pass to checkSwPool() when modeType equals "intermediate".
But this parameter is not used in that case.

- refactor and merge checkSwPool() and isAzOrIntermediateAvl() methods
- use checkSwPool() directly in initXndrTps()
- remove SERVICE_TYPE_100GE_S specific treatment

JIRA: TRNSPRTPCE-572
Signed-off-by: guillaume.lambert <guillaume.lambert@orange.com>
Change-Id: I0c7b0ba2f07fd904650a5d8ec456c326f1794c76