Make oemaids_headers available to vendor.

This change makes the oemaids_headers header library
available to vendor side.

Bug: 149665231
Test: Tested compilation, oemaids_headers is available to
a sample vendor binary.

Change-Id: I87369f1db883e40e83d6076defdd4c0d84aac46f

tools/fs_config/Android.bp

@@ -52,6 +52,7 @@ genrule {
 
 cc_library_headers {
     name: "oemaids_headers",
+    vendor_available: true,
     generated_headers: ["oemaids_header_gen"],
     export_generated_headers: ["oemaids_header_gen"],
 }