gdb: Convert language la_print_type field to a method

gdb: Convert language la_print_type field to a method

This commit changes the language_data::la_print_type function pointer
member variable into a member function of language_defn.

There should be no user visible changes after this commit.

gdb/ChangeLog:

	* ada-lang.c (ada_language_data): Delete la_print_type
	initializer.
	(ada_language::print_type): New member function.
	* c-lang.c (c_language_data): Delete la_print_type initializer.
	(c_language::print_type): New member function.
	(cplus_language_data): Delete la_print_type initializer.
	(cplus_language::print_type): New member function.
	(asm_language_data): Delete la_print_type initializer.
	(asm_language::print_type): New member function.
	(minimal_language_data): Delete la_print_type initializer.
	(minimal_language::print_type): New member function.
	* d-lang.c (d_language_data): Delete la_print_type initializer.
	(d_language::print_type): New member function.
	* f-lang.c (f_language_data): Delete la_print_type initializer.
	(f_language::print_type): New member function.
	* go-lang.c (go_language_data): Delete la_print_type initializer.
	(go_language::print_type): New member function.
	* language.c (unk_lang_print_type): Delete.
	(unknown_language_data): Delete la_print_type initializer.
	(unknown_language::print_type): New member function.
	(auto_language_data): Delete la_print_type initializer.
	(auto_language::print_type): New member function.
	* language.h (language_data): Delete la_print_type field.
	(language_defn::print_type): New function.
	(LA_PRINT_TYPE): Update.
	* m2-lang.c (m2_language_data): Delete la_print_type initializer.
	(m2_language::print_type): New member function.
	* objc-lang.c (objc_language_data): Delete la_print_type
	initializer.
	(objc_language::print_type): New member function.
	* opencl-lang.c (opencl_print_type): Delete, implementation moved
	to opencl_language::print_type.
	(opencl_language_data): Delete la_print_type initializer.
	(opencl_language::print_type): New member function, implementation
	from opencl_print_type.
	* p-lang.c (pascal_language_data): Delete la_print_type
	initializer.
	(pascal_language::print_type): New member function.
	* rust-lang.c (rust_print_type): Delete, implementation moved to
	rust_language::print_type.
	(rust_language_data): Delete la_print_type initializer.
	(rust_language::print_type): New member function, implementation
	from rust_print_type.