base_image_util: Tolerate multiple ARM kernels

Shell '-e' test can only be used on a single file name,
so if the glob matches multiple kernels, no kernels will be copied!

BUG=b/283954538
TEST=`build_image --board=gmec-arm64-hw` (to be committed)
RELEASE_NOTE=None

Change-Id: Ie200c5b051849533c98fc4a8e16a61b6ca9b612b
Reviewed-on: https://cos-review.googlesource.com/c/third_party/platform/crosutils/+/49831
Tested-by: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>
Reviewed-by: Meena Shanmugam <meenashanmugam@google.com>
diff --git a/build_library/base_image_util.sh b/build_library/base_image_util.sh
index 849a3e3..c6786f3 100755
--- a/build_library/base_image_util.sh
+++ b/build_library/base_image_util.sh
@@ -618,7 +618,7 @@
     sudo "${cpmv}" "${boot_dir}"/Image-* "${BUILD_DIR}/boot_images"
   [ -L "${boot_dir}"/zImage-* ] && \
     sudo "${cpmv}" "${boot_dir}"/zImage-* "${BUILD_DIR}/boot_images"
-  [ -e "${boot_dir}"/vmlinuz-* ] && \
+  find "${boot_dir}"/vmlinuz-* >/dev/null 2>&1 && \
     sudo "${cpmv}" "${boot_dir}"/vmlinuz-* "${BUILD_DIR}/boot_images"
   [ -L "${boot_dir}"/vmlinuz ] && \
     sudo "${cpmv}" "${boot_dir}"/vmlinuz "${BUILD_DIR}/boot_images"