c: Refactor c_parser_unary_expression()

c: Refactor c_parser_unary_expression()

Store the 'rid' value in a local variable, and pass it to functions that
handle various keywords.  This simplifies the code, and removes some
wrappers.

No functional change intended.

gcc/c/ChangeLog:

	* c-parser.cc (c_parser_sizeof_expression): Remove function.
	(c_parser_countof_expression): Remove function.
	(c_parser_unary_expression): Store the 'rid', and pass it
	directly to the function calls, without calling wrappers.

Suggested-by: Andrew Pinski <andrew.pinski@oss.qualcomm.com>
Signed-off-by: Alejandro Colomar <alx@kernel.org>