make.sh: Fix typo

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>

diff --git a/make.sh b/make.sh
index c0880573f78df8dbb788fa6dbc60398dd147eb3e..84278392227194ccfce7dc56f3bfba827e66dd94 100755 (executable)
--- a/make.sh
+++ b/make.sh
@@ -391,7 +391,7 @@ exiterror() {
 
 prepareenv() {
        # Are we running the right shell?
-       if [ ! -z "${BASH}" ]; then
+       if [ -z "${BASH}" ]; then
                exiterror "BASH environment variable is not set.  You're probably running the wrong shell."
        fi