Rename payload metadata partition

/dev/block/by-name/metadata is used by others as well.

Renamed it as payload-metadata.

Bug: 191097666
Test: MicrodroidHostTestCases
Change-Id: I873ee2acbe38772e59c96b3904023ac0d1573621
diff --git a/microdroid/payload/metadata/Android.bp b/microdroid/payload/metadata/Android.bp
index d3ec625..e4c7692 100644
--- a/microdroid/payload/metadata/Android.bp
+++ b/microdroid/payload/metadata/Android.bp
@@ -10,6 +10,7 @@
     prefer_rlib: true,
     edition: "2018",
     rustlibs: [
+        "libanyhow",
         "libmicrodroid_metadata_proto_rust",
         "libprotobuf",
     ],