make.sh: Fix typo

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

diff --git a/make.sh b/make.sh
index b20e7073d4384b9d0ce5195238fad328e8db7f6f..1a4064072e96c7c66ef2cd498128fa06e7f193e9 100755 (executable)
--- a/make.sh
+++ b/make.sh
@@ -428,7 +428,7 @@ 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