Add erofs compression param

Test: th
Bug: 206729162
Change-Id: I774918693262c8e48a2656d82d5acaeb4e3aaed2
diff --git a/scripts/brillo_update_payload b/scripts/brillo_update_payload
index f9c70f3..b2d6080 100755
--- a/scripts/brillo_update_payload
+++ b/scripts/brillo_update_payload
@@ -218,6 +218,8 @@
     "Optional: Whether to enable lz4 diffing for EROFS"
   DEFINE_string liblz4_path "" \
     "Required if --enabled_lz4diff true is passed. Path to liblz4.so. delta_generator will use this copy of liblz4.so for compression. It is important that this copy of liblz4.so is the same as the one on source build."
+  DEFINE_string erofs_compression_param "" \
+    "Compression parameter passed to mkfs.erofs's -z option."
 fi
 if [[ "${COMMAND}" == "hash" || "${COMMAND}" == "sign" ]]; then
   DEFINE_string unsigned_payload "" "Path to the input unsigned payload."
@@ -741,6 +743,10 @@
       GENERATOR_ARGS+=(
         --enable_lz4diff="${FLAGS_enable_lz4diff}" )
     fi
+    if [[ -n "${FLAGS_erofs_compression_param}" ]]; then
+      GENERATOR_ARGS+=(
+        --erofs_compression_param="${FLAGS_erofs_compression_param}" )
+    fi
   fi
 
   if [[ -n "${FLAGS_enable_vabc_xor}" ]]; then