Move POSNAME from IAL (ifs-source) to fiat

[AlexandreMary]

Is your feature request related to a problem? Please describe.

One circular dependency between IAL's arpifs and phyex sub-projects (the latter to be fully externalised in an upcoming MF/ACCORD cycle) is that phyex uses POSNAM[E] (arpifs/utility/posnam[e].F90).

(Note there is another circular dependency between these 2, being fixed in CY50T1)

Describe the solution you'd like

Solution: Move POSNAME into fiat (and call POSNAME instead of POSNAM from phyex).

POSNAM uses YOMLUN (NULOUT) so it should probably stay in IAL, but an optional dummy argument KULOUT could be passed to POSNAME for the prints, together with a LFATAL optional dummy argument to call ABOR1 in the case where POSNAM does.
POSNAM would then be modified to become a very shallow wrapping, calling POSNAME with KULOUT=NULOUT and LFATAL=.TRUE.

Describe alternatives you've considered

No response

Additional context

No response

Organisation

No response

[AlexandreMary]

If consensus, I can implement that in sight of CY50T1 (and provide the commit in IAL/ifs-source to remove POSNAM from it and avoid symbol duplication).