coqdep: Warning about ml file clashes, keeping the file corresponding
to the first -I option.

Fortunately, with -I option, only one file can be found by occurrence
of the option, so on the contrary of -Q/-R options for v files, the
order is not file-system dependent.
coqdep: granting #2506 (./dir is the same as dir)
Reactivating option "Set Printing Existential Instances" for asking printing full instances.