openmp: Metadirective fixes

openmp: Metadirective fixes

Fix regressions introduced by block/statement skipping.

If user condition selector is constant, do not return it as a dynamic
selector.

2022-01-25  Kwok Cheung Yeung  <kcy@codesourcery.com>

	gcc/c/
	* c-parser.c (c_parser_skip_to_end_of_block_or_statement): Track
	bracket depth separately from nesting depth.

	gcc/cp/
	* parser.c (cp_parser_skip_to_end_of_statement): Revert.
	(cp_parser_skip_to_end_of_block_or_statement): Track bracket depth
	separately from nesting depth.

	gcc/
	* omp-general.c (omp_dynamic_cond): Do not return user condition if
	constant.