Fortran: fix check of polymorphic elements in data transfers [PR100971]

gcc/fortran/ChangeLog:

	PR fortran/100971
	* resolve.cc (resolve_transfer): Extend check for permissibility
	of polymorphic elements in a data transfer to arrays.

gcc/testsuite/ChangeLog:

	PR fortran/100971
	* gfortran.dg/der_io_5.f90: New test.