kconfig: nuke LKC_DIRECT_LINK cruft

This interface is not (and has never been ?) used by any frontend, just get rid
of it.

Signed-off-by: Arnaud Lacombe <lacombar@gmail.com>

scripts/kconfig/kxgettext.c

@@ -7,7 +7,6 @@
 #include <stdlib.h>
 #include <string.h>
 
-#define LKC_DIRECT_LINK
 #include "lkc.h"
 
 static char *escape(const char* text, char *bf, int len)