kconfig: kconfig_warnings needs to be defined for all frontends

Change-Id: Iecefdd1e827e4eb8b4da573e4291850d6c47767f
Signed-off-by: Patrick Georgi <patrick@georgi-clan.de>
Reviewed-on: http://review.coreboot.org/11754
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Werner Zeh <werner.zeh@siemens.com>

util/kconfig/mconf.c

@@ -22,6 +22,8 @@
 #include "lkc.h"
 #include "lxdialog/dialog.h"
 
+int kconfig_warnings = 0;
+
 static const char mconf_readme[] = N_(
 "Overview\n"
 "--------\n"

util/kconfig/nconf.c

@@ -13,6 +13,8 @@
 #include "nconf.h"
 #include <ctype.h>
 
+int kconfig_warnings = 0;
+
 static const char nconf_global_help[] = N_(
 "Help windows\n"
 "------------\n"