OpenMP: Duplicate checking for map clauses in Fortran (PR107214)

OpenMP: Duplicate checking for map clauses in Fortran (PR107214)

This patch adds duplicate checking for OpenMP "map" clauses, taking some
cues from the implementation for C in c-typeck.cc:c_finish_omp_clauses
(and similar for C++).

In addition to the existing use of the "mark" and "comp_mark" bitfields
in the gfc_symbol structure, the patch adds several new bits handling
duplicate checking within various categories of clause types.  If "mark"
is being used for map clauses, we need to use different bits for other
clauses for cases where "map" and some other clause can refer to the
same symbol (e.g. "map(n) shared(n)").

2022-12-06  Julian Brown  <julian@codesourcery.com>

gcc/fortran/
	PR fortran/107214
	* gfortran.h (gfc_symbol): Add data_mark, dev_mark, gen_mark and
	reduc_mark bitfields.
	* openmp.cc (resolve_omp_clauses): Use above bitfields to improve
	duplicate clause detection.

gcc/testsuite/
	PR fortran/107214
	* gfortran.dg/gomp/pr107214.f90: New test.
	* gfortran.dg/gomp/pr107214-2.f90: New test.
	* gfortran.dg/gomp/pr107214-3.f90: New test.
	* gfortran.dg/gomp/pr107214-4.f90: New test.
	* gfortran.dg/gomp/pr107214-5.f90: New test.
	* gfortran.dg/gomp/pr107214-6.f90: New test.
	* gfortran.dg/gomp/pr107214-7.f90: New test.
	* gfortran.dg/gomp/pr107214-8.f90: New test.