Make libaconfig_storage_read_api rust lib vendor available.

Newly introduced vendor process ueventmond, written in rust, depends on
aconfig library to have access to aconfig flags.

Flag: EXEMPT Make library vendor available.
BUG: 402539394
Test: Presubmit
Change-Id: Ib3b7255454fa2b03992fce1028cc8503ef80a339