..trusted OS directory

documentation/optee_design.md was recently removed in a patch upstream
so use another file less likely to be removed again.

Signed-off-by: Victor Chong <victor.chong@linaro.org>
---

v2: update commit message to fix filename typo

---
 opteed-build.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/opteed-build.sh b/opteed-build.sh
index 2dd40ff..3229cbb 100755
--- a/opteed-build.sh
+++ b/opteed-build.sh
@@ -126,7 +126,7 @@ function build_platform

 # Check to see if we are in a trusted OS directory
 # refuse to continue if we aren't
-if [ ! -f documentation/optee_design.md ]
+if [ ! -f core/tee/tee_svc.c ]
 then
        echo "ERROR: we aren't in the optee_os directory."
        usage
--
2.17.1