build_image_util: Set --with-bdeps=n to exclude EDEPEND.

We do not need to install BDEPEND when emerging to an image.

BUG=b:198621763
TEST=./build_packages --board=${BOARD} && ./build_image --board=${BOARD}

Change-Id: I5686f2994144cef6c36165d7813f4deed36572aa
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosutils/+/3138768
Reviewed-by: Chris McDonald <cjmcdonald@chromium.org>
Tested-by: Allen Webb <allenwebb@google.com>
Commit-Queue: Allen Webb <allenwebb@google.com>
diff --git a/build_library/build_image_util.sh b/build_library/build_image_util.sh
index 3d142c9..5b2d72f 100755
--- a/build_library/build_image_util.sh
+++ b/build_library/build_image_util.sh
@@ -194,7 +194,7 @@
 # Arguments to this command are passed as addition options/arguments
 # to the basic emerge command.
 emerge_to_image() {
-  set -- ${EMERGE_BOARD_CMD} --root-deps=rdeps --usepkgonly -v \
+  set -- ${EMERGE_BOARD_CMD} --root-deps=rdeps --usepkgonly -v --with-bdeps=n \
     "$@" ${EMERGE_JOBS}
   info "$*"
   sudo -E "$@"