bug#3207: 23.0.93; x-display-planes is incorrect in NS port

[Ian Eure <ian@digg.com>]

When starting up NextStep Emacs compiled from CVS HEAD, the old XPM  
splash image is used, rather than the new PNG.

This appears to be caused by (display-planes) reporting an eight-plane  
display. This is almost certainly incorrect.

Looking deeper, (display-planes) calls (x-display-planes), in nsfns.m.  
I don’t see anything obviously wrong, but it’s reporting that I have  
an 8-plane display when it’s 24-plane. Evaluating (x-display-color- 
cells) produces the correct value: 16777216, indicating a 24-bit  
display.

In GNU Emacs 23.0.93.1 (i386-apple-darwin9.6.0, NS apple-appkit-949.43)
  of 2009-05-04 on neutron.local
Windowing system distributor `Apple', version 10.3.949
configured using `configure  '--with-ns''

Important settings:
   value of $LC_ALL: nil
   value of $LC_COLLATE: nil
   value of $LC_CTYPE: nil
   value of $LC_MESSAGES: nil
   value of $LC_MONETARY: nil
   value of $LC_NUMERIC: nil
   value of $LC_TIME: nil
   value of $LANG: nil
   value of $XMODIFIERS: nil
   locale-coding-system: nil
   default-enable-multibyte-characters: t

Major mode: Lisp Interaction

Minor modes in effect:
   diff-auto-refine-mode: t
   erc-track-mode: t
   erc-track-minor-mode: t
   erc-spelling-mode: t
   erc-ring-mode: t
   erc-pcomplete-mode: t
   erc-netsplit-mode: t
   erc-match-mode: t
   erc-button-mode: t
   erc-fill-mode: t
   erc-autojoin-mode: t
   erc-irccontrols-mode: t
   erc-noncommands-mode: t
   erc-readonly-mode: t
   erc-scrolltobottom-mode: t
   goto-address-prog-mode: t
   light-symbol-mode: t
   hl-line-mode: t
   eldoc-mode: t
   which-function-mode: t
   yas/minor-mode: t
   ime-bindings: t
   shell-dirtrack-mode: t
   show-paren-mode: t
   recentf-mode: t
   iswitchb-mode: t
   cua-mode: t
   auto-insert-mode: t
   tooltip-mode: t
   mouse-wheel-mode: t
   menu-bar-mode: t
   file-name-shadow-mode: t
   global-font-lock-mode: t
   font-lock-mode: t
   blink-cursor-mode: t
   global-auto-composition-mode: t
   auto-composition-mode: t
   auto-encryption-mode: t
   auto-compression-mode: t
   size-indication-mode: t
   column-number-mode: t
   line-number-mode: t
   transient-mark-mode: t
   abbrev-mode: t

Recent input:
i s p l a y - l <backspace> p l a n e s C-e C-x C-e
C-x o C-n C-p C-p M-m C-p C-p M-m C-n C-n C-f C-f M-m
C-x o M-b M-d c o l o r - p C-e C-x C-e C-x o C-n C-n
M-m C-p C-f C-f C-f C-x o C-a C-k <down-mouse-1> <mouse-1>
<down-mouse-1> <mouse-1> <switch-frame> l e o <tab>
SPC L o o k s SPC l i k e SPC N S SPC g e t s SPC t
h e SPC X P M SPC b e c a u s e SPC M-( d s i a p l
y <M-backspace> d i s p l a M-b C-b C-b C-k SPC i t
SPC t h i n k s SPC i t SPC h o <backspace> <backspace>
o n l y SPC h a s SPC 9 <backspace> 8 - b i t SPC c
l o l C-x C-g <switch-frame> C-h f d i s p l <tab>
- l <backspace> <backspace> p l <tab> <return> <switch-frame>
<backspace> <backspace> <backspace> o l o r SPC f o
r SPC s o m e SPC r e a s o n , <return> <switch-frame>
<down-mouse-1> <mouse-movement> <mouse-1> <help-echo>
<help-echo> <down-mouse-1> <mouse-1> <down-mouse-1>
<mouse-1> <switch-frame> <switch-frame> <down-mouse-1>
<mouse-1> <help-echo> <switch-frame> <switch-frame>
C-x b <return> <help-echo> <down-mouse-1> <mouse-1>
<down-mouse-1> <mouse-1> <down-mouse-1> <mouse-1> <down-mouse-1>
<mouse-1> M-( l e t SPC M-( M-( f a n c e y <backspace>
<backspace> y M-/ M-/ SPC M-" s p l a s h . p n g C-e
C-b <return> C-x o C-x o M-( f a n c y - s p l a s
h - h e a d C-e C-x C-e <help-echo> <down-mouse-1>
<mouse-1> <menu-bar> <help-menu> <send-emacs-bug-r
eport>

Recent messages:
8
Evaluating...
Mark set
t
Type C-x 4 C-o RET to restore the other window.
Scanning for dabbrevs...100%
Expansion found in 'startup.el.gz'
Evaluating...
Mark set
nil