kconfig: remove lkc_defs.h from .gitignore and dontdiff

Commit 5a6f8d2bd9e3392569ed6f29ea4d7210652f929b ("kconfig: nuke
LKC_DIRECT_LINK cruft") removed all traces of lkc_defs.h from the tree.
Remove its entries in dontdiff and kconfig's .gitignore file too.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Michal Marek <mmarek@suse.cz>

Documentation/dontdiff

@@ -150,7 +150,6 @@ keywords.c
 ksym.c*
 ksym.h*
 kxgettext
-lkc_defs.h
 lex.c
 lex.*.c
 linux

scripts/kconfig/.gitignore

@@ -7,7 +7,6 @@ config*
 *.tab.h
 zconf.hash.c
 *.moc
-lkc_defs.h
 gconf.glade.h
 *.pot
 *.mo