randomconfig fixes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/testsuite/mdev.tests b/testsuite/mdev.tests
index 48d3dcc..5987301 100755
--- a/testsuite/mdev.tests
+++ b/testsuite/mdev.tests
@@ -168,7 +168,7 @@
 # continuing to use directory structure from prev test
 rm -rf mdev.testdir/dev/*
 echo "sda 0:0 644 @echo @echo TEST" >mdev.testdir/etc/mdev.conf
-optional STATIC FEATURE_MDEV_CONF FEATURE_MDEV_EXEC FEATURE_LS_RECURSIVE FEATURE_LS_TIMESTAMPS FEATURE_LS_USERNAME FEATURE_SH_IS_ASH
+optional STATIC FEATURE_MDEV_CONF FEATURE_MDEV_EXEC FEATURE_LS_RECURSIVE FEATURE_LS_TIMESTAMPS FEATURE_LS_USERNAME FEATURE_SH_IS_ASH ASH_BUILTIN_ECHO
 testing "mdev command" \
 	"env - PATH=$PATH ACTION=add DEVPATH=/block/sda chroot mdev.testdir /mdev 2>&1;
 	ls -lnR mdev.testdir/dev | $FILTER_LS" \