mkosi-obs: also check that ESP offset is not an empty string

Can also happen, not just 'null'

diff --git a/mkosi/resources/mkosi-obs/mkosi.build b/mkosi/resources/mkosi-obs/mkosi.build
index 7fbe3c7df9f2100d3a8b0f0b83d3f0fe950de33a..c59717106af32a635f66a200e31fe1a41eb0426d 100755 (executable)
--- a/mkosi/resources/mkosi-obs/mkosi.build
+++ b/mkosi/resources/mkosi-obs/mkosi.build
@@ -66,7 +66,7 @@ while read -r SIG; do
             unzstd "${DEST%efi}raw.zst"
         fi
         offset="$(systemd-repart --json=short "${DEST%efi}raw" | jq -r '.[] | select(.type == "esp") | .offset')"
-        if [ "$offset" = "null" ]; then
+        if [ -z "$offset" ] || [ "$offset" = "null" ]; then
             rm -f "${DEST%efi}raw"
             continue
         fi