ProcedureCreate formerly threw an error if the function to be created
has one argument of composite type and the function name matches some
column of the composite type.  This was a (very non-bulletproof) defense
against creating situations where f(x) and x.f are ambiguous.  But we
don't really need such a defense in the wake of commit b97a3465, which
allows us to deal with such situations fairly cleanly.  This behavior
also created a dump-and-reload hazard, since a function might be
rejected if a conflicting column name had been added to the input
composite type later.  Hence, let's just drop the check.

Discussion: https://postgr.es/m/CAOW5sYa3Wp7KozCuzjOdw6PiOYPi6D=VvRybtH2S=2C0SVmRmA@mail.gmail.com