Add /data/vendor/lib as a library location under ASan.

This is in addition to /data/lib.
Only affects SANITIZE_TARGET=address builds.

Bug: 21785137
Change-Id: Id1983cabb9479ae2d38fb23691de3eba236fe9cb

file_contexts_asan

-/data/lib(/.*)?		u:object_r:system_file:s0
+/data/lib(/.*)?                u:object_r:system_file:s0
+/data/vendor/lib(/.*)?         u:object_r:system_file:s0