grub.cfg: updated linux cmdline

the locale options were not recognized properly.

grub/grub.cfg

@@ -74,7 +74,7 @@ function LoadCasper {
 }
 
 menuentry "Empfohlen: ${lip_flavor} ${lip_version}${lip_extra_info} ${bits}bit (deutsch)" {
-	set cmdline="debian-installer/locale=de_DE console-setup/layoutcode=de"
+	set cmdline="debian-installer/language=de keyboard-configuration/layoutcode?=de"
 	LoadCasper
 }