[cc_fuzz] Export DSO symbols to /symbols/data/

cc_fuzz reexports transient dependeny DSO's to /data/fuzz through Make.
We intentionally export the non-stripped variants so that ClusterFuzz
can use the symbolized variant, but we don't re-export to
/symbols/data/fuzz. This means that tools like `stack` and
`hwasan_symbolize` can't pick up the symbols and don't know what to do.

Fix this by re-exporting to /symbols/ as well.

Bug: N/A
Test: make example_fuzzer && ls
$ANDROID_PRODUCT_OUT/symbols/data/fuzz/arm64/lib

Change-Id: Id0343c95a0a83e16e6f67f29ff6361fb4d757c05