scripts/kernel-doc: fix fatal error caused by cfg80211.h

include/net/cfg80211.h uses __must_check in functions that
have kernel-doc notation.  This was confusing scripts/kernel-doc,
so have scripts/kernel-doc ignore "__must_check".

Error(include/net/cfg80211.h:2702): cannot understand prototype: 'struct cfg80211_bss * __must_check cfg80211_inform_bss(...)

Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Cc:	Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Author: rddunlap

scripts/kernel-doc

@@ -5,7 +5,7 @@ use strict;
 ## Copyright (c) 1998 Michael Zucchi, All Rights Reserved        ##
 ## Copyright (C) 2000, 1  Tim Waugh <twaugh@redhat.com>          ##
 ## Copyright (C) 2001  Simon Huggins                             ##
-## Copyright (C) 2005-2010  Randy Dunlap                         ##
+## Copyright (C) 2005-2012  Randy Dunlap                         ##
 ## 								 ##
 ## #define enhancements by Armin Kuster <akuster@mvista.com>	 ##
 ## Copyright (c) 2000 MontaVista Software, Inc.			 ##
@@ -1785,6 +1785,7 @@ sub dump_function($$) {
     $prototype =~ s/__devinit +//;
     $prototype =~ s/__init +//;
     $prototype =~ s/__init_or_module +//;
+    $prototype =~ s/__must_check +//;
     $prototype =~ s/^#\s*define\s+//; #ak added
     $prototype =~ s/__attribute__\s*\(\([a-z,]*\)\)//;