Module incorrectly marked dead when contains non-dead type and submodule definitions

[sim642]

Running reanalyze 389dd68 on Goblint goblint/analyzer@a544002 revealed the following.

In the terminal output there's a dead module warning:

  Warning Dead Module
  File "./gobview/src/state/gvMessages.ml", line 1, characters 0-0
  +gvMessages is a dead module as all its items are dead.

  Warning Dead Value
  File "./gobview/src/state/gvMessages.ml", lines 22-28, characters 0-18
  +filter_by_line is never used
  <-- line 22
    List.filter pred [@@dead "+filter_by_line"]

Although the only value filter_by_line is indeed dead, it also contains a type t and module Message which are not. Therefore the GvMessages module should not be considered dead overall.

[cristianoc]

Not sure if include is treated correctly, for the inner module.