Some writediagfi() in physiq are shadowed under an if(callstats) flag

[emillour]

I realised that in physiq_mod.F the "call writediagfi" for vmr (vmr_xxx) and number density (num_xxx) is inside the IF(callstats). It means that if the user select callstats =.false. in callphys.def, because he/she doesn't need to use stats* files and occupy unnecessary space on the machine, the outputs diagfi*nc will not contain all the variable in diagfi.def, notably the number density and the vmr.

Also mentionned on:
​https://gitlab.in2p3.fr/la-communaut-des-mod-les-atmosph-riques-plan-taires/git-trunk/-/issues/23

This was solved with r2563, since the "callstats" flag is now checked from within the wstats routine.