[OpenMP, Fortran] Add structure/derived-type element mapping

[OpenMP, Fortran] Add structure/derived-type element mapping

gcc/fortran/ChangeLog:

	* openmp.c (gfc_match_omp_clauses): Match also derived-type
	component refs in OMP_CLAUSE_MAP.
	(resolve_omp_clauses): Resolve those.
	* trans-openmp.c (gfc_trans_omp_array_section, gfc_trans_omp_clauses):
	Handle OpenMP structure-element mapping.
	(gfc_trans_oacc_construct, gfc_trans_oacc_executable_directive,
	(gfc_trans_oacc_combined_directive, gfc_trans_oacc_declare): Update
	add openacc=true in gfc_trans_omp_clauses call.

gcc/testsuite/ChangeLog:

	* gfortran.dg/goacc/finalize-1.f: Update dump scan pattern.
	* gfortran.dg/gomp/map-1.f90: Update dg-error.
	* gfortran.dg/gomp/map-2.f90: New test.

libgomp/ChangeLog:

	* testsuite/libgomp.fortran/struct-elem-map-1.f90: New test.