bug#3888: Some variables get the wrong, platform-specific, documentation

[Glenn Morris]

In GNU Emacs 23.0.96.1 on GNU/Linux:

emacs -Q
C-h v x-select-enable-clipboard

    x-select-enable-clipboard is a variable defined in `x-win.el'.
    Its value is nil

    Documentation:
    Non-nil means cutting and pasting uses the clipboard.
    This is the default on this system, since MS-Windows does not
    support other types of selections.

I guess this is because term/pc-win.elc is now in SOME_MACHINE_LISP in
src/Makefile.in. (It was not there in Emacs 22.)


Similarly, from ns-win.el, we get the following in GNU/Linux under X:

    x-display-name:
    The name of the Nextstep display on which Emacs was started.

    x-setup-function-keys:
    Set up function Keys for Nextstep for frame FRAME.

    x-select-text:
    Put TEXT, a string, on the pasteboard.

    x-colors:
    The list of colors defined in non-PANTONE color files.

    xw-defined-colors:
    Return a list of colors supported for a particular frame.
    The argument FRAME specifies which frame to try.
    The value may be different for frames on different Nextstep displays.