OpenMP/Fortran: Handle polymorphic scalars in data-sharing FIRSTPRIVATE [PR86470]

OpenMP/Fortran: Handle polymorphic scalars in data-sharing FIRSTPRIVATE [PR86470]

gcc/fortran/ChangeLog:

	PR fortran/86470
	* trans-expr.c (gfc_copy_class_to_class): Add unshare_expr.
	* trans-openmp.c (gfc_is_polymorphic_nonptr,
	gfc_is_unlimited_polymorphic_nonptr): New.
	(gfc_omp_clause_copy_ctor, gfc_omp_clause_dtor): Handle
	polymorphic scalars.

libgomp/ChangeLog:

	PR fortran/86470
	* testsuite/libgomp.fortran/class-firstprivate-1.f90: New test.
	* testsuite/libgomp.fortran/class-firstprivate-2.f90: New test.
	* testsuite/libgomp.fortran/class-firstprivate-3.f90: New test.

gcc/testsuite/ChangeLog:

	PR fortran/86470
	* gfortran.dg/gomp/class-firstprivate-1.f90: New test.
	* gfortran.dg/gomp/class-firstprivate-2.f90: New test.
	* gfortran.dg/gomp/class-firstprivate-3.f90: New test.
	* gfortran.dg/gomp/class-firstprivate-4.f90: New test.