Check for make failure

src/freedombone-image

     SSH_PUBKEY="$SSH_PUBKEY" \
     GENERIC_IMAGE="$GENERIC_IMAGE"
 
+if [ ! "$?" = "0" ]; then
+    echo 'Build failed'
+    rm -rf $BUILD_DIR
+    exit 1
+fi
+
 EXPECTED_EXTENSION='img'
 if [[ $IMAGE_TYPE == "qemu"* ]]; then
     EXPECTED_EXTENSION='qcow2'
 if [ ${#imgfiles[@]} -eq 0 ]; then
     echo 'Image was not created'
     rm -rf $BUILD_DIR
-    exit 1
+    exit 2
 fi
 
 mv build/${PROJECT_NAME}*.bz2 ${CURR_DIR}