This patch fixes a regression introduced in commit
d15cfafeef8f99ff1a47e77362d0adf1b07f26ae.

While there, use "-z" to check if ubiroot variable is empty.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Cc: Eric B�nard <eric@eukrea.com>
---
 defaultenv/bin/boot |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/defaultenv/bin/boot b/defaultenv/bin/boot
index fa68748..788a781 100644
--- a/defaultenv/bin/boot
+++ b/defaultenv/bin/boot
@@ -34,8 +34,8 @@ else
 	fi
 
 	if [ x$rootfs_type = xubifs ]; then
-		if [ x$ubiroot = x ]; then
-			ubiroot = "root"
+		if [ -z $ubiroot ]; then
+			ubiroot="root"
 		fi
 		bootargs="$bootargs root=ubi0:$ubiroot ubi.mtd=$rootfs_mtdblock"
 	else
-- 
1.7.2.3