c++: Fix scan forward over pragma [PR96257]

c++: Fix scan forward over pragma [PR96257]

It turns out that the paren scanning code is used for speculatively searching
to see if we're looking at a compound_literal.  So we shouldn't always purge
pragma tokens.

	gcc/cp/
	* parser.c (cp_lexer_consume_token): Drop PRAGMA_EOL assert.
	(cp_parser_skip_to_closing_parenthesis_1): Only pass start token
	to pragma skipper if recovering.
	(cp_parser_skip_to_pragma_eol): Only purge and change pragma
	state when recovering.
	gcc/testsuite/
	* g++.dg/parse/pr96257.C: New.