Move check for image until we actually need it.

mod_image_for_test.sh

Index: mod_image_for_test.sh
diff --git a/mod_image_for_test.sh b/mod_image_for_test.sh
index b9f123fb0aa51536231f72414bacef3d8b18a853..822a293262469837388005b2d7d25b4eba9378f1 100755
--- a/mod_image_for_test.sh
+++ b/mod_image_for_test.sh
@@ -87,12 +87,6 @@ fi
 # Turn path into an absolute path.
 FLAGS_image=`eval readlink -f ${FLAGS_image}`
 
-# Abort early if we can't find the image
-if [ ! -f $FLAGS_image ] ; then
-  echo "No image found at $FLAGS_image"
-  exit 1
-fi
-
 # What cross-build are we targeting?
 . "${FLAGS_build_root}/${FLAGS_board}/etc/make.conf.board_setup"
 # Figure out ARCH from the given toolchain.
@@ -214,6 +208,11 @@ else
   echo "Modifying image ${FLAGS_image} for test..."
 fi
 
+# Abort early if we can't find the image
+if [ ! -f $FLAGS_image ] && [ ${FLAGS_inplace} -eq ${FLAGS_TRUE} ; then
+  die "No image found at $FLAGS_image to modify"
+fi
+
 set -e
 
 IMAGE_DIR=$(dirname "$FLAGS_image")