Turn parse_gdbarch into a method

Turn parse_gdbarch into a method

This changes parse_gdbarch into a method of parser_state.  This patch
was written by a script.

gdb/ChangeLog
2019-04-04  Tom Tromey  <tom@tromey.com>

	* rust-exp.y: Replace "parse_gdbarch" with method call.
	* parse.c (write_dollar_variable, insert_type_address_space):
	Replace "parse_gdbarch" with method call.
	* p-exp.y (parse_type, yylex): Replace "parse_gdbarch" with method
	call.
	* objc-lang.c (end_msglist): Replace "parse_gdbarch" with method
	call.
	* m2-exp.y (parse_type, parse_m2_type, yylex): Replace
	"parse_gdbarch" with method call.
	* go-exp.y (parse_type, classify_name): Replace "parse_gdbarch"
	with method call.
	* f-exp.y (parse_type, parse_f_type, yylex): Replace
	"parse_gdbarch" with method call.
	* d-exp.y (parse_type, parse_d_type, lex_one_token): Replace
	"parse_gdbarch" with method call.
	* c-exp.y (parse_type, parse_number, classify_name): Replace
	"parse_gdbarch" with method call.
	* ada-lex.l: Replace "parse_gdbarch" with method call.
	* ada-exp.y (parse_type, find_primitive_type, type_char)
	(type_system_address): Replace "parse_gdbarch" with method call.