Dear all,

here's the second part of a series for the treatment of missing
optional arguments passed to optional dummies, now fixing the
case that the latter procedures are elemental.  Adjustments
were necessary when the missing dummy has the VALUE attribute.

I factored the code for the treatment of VALUE, hoping that the
monster loop in gfc_conv_procedure_call will become slightly
easier to overlook.

Regtested on x86_64-pc-linux-gnu.  OK for mainline?

Thanks,
Harald