Fix handling of tool-bar-position, also put into default-frame-alist.

Fix handling of tool-bar-position, also put into default-frame-alist.

* lisp/menu-bar.el (menu-bar-set-tool-bar-position): New function.
(menu-bar-showhide-tool-bar-menu-customize-enable-left)
(menu-bar-showhide-tool-bar-menu-customize-enable-right)
(menu-bar-showhide-tool-bar-menu-customize-enable-top)
(menu-bar-showhide-tool-bar-menu-customize-enable-bottom): Call
menu-bar-set-tool-bar-position.

* src/frame.h (Qtool_bar_position): Declare.

* src/xfns.c (Fx_create_frame): Call x_default_parameter for
Qtool_bar_position.