kconfig/conf: merge duplicate switch's case

Signed-off-by: NArnaud Lacombe <lacombar@gmail.com>
Signed-off-by: NMichal Marek <mmarek@suse.cz>

scripts/kconfig/conf.c

@@ -529,8 +529,6 @@ int main(int ac, char **av)
 		}
 		break;
 	case savedefconfig:
-		conf_read(NULL);
-		break;
 	case silentoldconfig:
 	case oldaskconfig:
 	case oldconfig: