vm_insnhelper.c: rb_autoloading_value flag

	* vm_insnhelper.c (vm_get_ev_const): add flag argument of
	  `rb_autoloading_value`.

	* constant.h (rb_autoloading_value): moved the declaration from
	  vm_core.h for `rb_const_flag_t`.  [ruby-core:85516] [Bug #14469]

	variable.c: flags at autoloading

	* variable.c (const_tbl_update): flags by deprecate_constant /
	  private_constant set during autoloading should be preserved
	  after required.  [ruby-core:85516] [Bug #14469]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_4@62916 b2dd03c8-39d4-4d8f-98ff-823fe69b080e