[Bug tree-optimization/65488] parloops runs for functions it doesn't process

[vries at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65488

--- Comment #1 from vries at gcc dot gnu.org ---
After committing the fix for PR65487, moving !parallelized_function_p
(fun->decl) and !fun->has_nonlocal_label to the gate function doesn't give any
interference anymore with -fdump-passes.

In order to move (number_of_loops (fun) > 1) to the gate function without
changing fdump-passes output, we need to add a dummy loop to the dummy function
used as context in pass_manager::dump_passes ().