build-release: only zip files, not directories

Zip format does not require to store directory to store files
in a directory. Storing directory is only required for storing
directory metadata (like file modification date, etc.)

Not storing directories produces smaller zip files, the directories
are automatically created when unzipping the files.

Author: illwieckz

build-release

@@ -241,7 +241,11 @@ package () {
 			rm -v "${archive_filename}"
 		fi
 
-		7z -mx='9' -t"${archive_format}" a "${archive_filename}" .
+		# Only store files, not folders, folders will be recreated on extraction.
+		local file_list="$(mktemp)"
+		find . -type f | cut -c3- | sort > "${file_list}"
+		7z -mx='9' -snl -t"${archive_format}" a "${archive_filename}" -i@"${file_list}"
+		rm "${file_list}"
 	)
 }