Install cross partition symlinks in autogenerated vendor.img

These match the symlinks present in the kati built vendor.img file.

Since structs are not supported in `generateBpContent`, Android.bp
generation for vendor is skipped for now.

Bug: 374371755
Test: Verified that odm and lib/modules are present in vendor.img's
fileList for aosp_cf_x86_64_phone

Change-Id: I2564d23a5fc3b8e1aad360373ff2c103a074cfe7