Floating invalid in p4zopt.f90 without RGB traqsr

I first guessed that I encountered the same issue as reported on the forum, but in fact, it is different because in my case, I am not using RGB solar penetration scheme, so the bug is not related. The issue in the forum has been reproduced by @tlovato in the discussion below and is due to the presence of bad chl values (NaN) for unknown reasons.

In my specific case, I have to add the init of rkrgb variable in traqsr.F90 when using the 2-bands traqsr scheme with PISCES (online), because PISCES needs this array to compute its own solar penetration.