Remove support for dexopting shared libraries.

The CL landed after feature complete, and has shown it can cause related issues,
not easy to deal with (eg b/128529256 or b/128912573).

The libs are expected to be preopted (as in P).

Partial revert of 653356f1.

Test: BackgroundDexOptServiceIntegrationTests
Test: DexoptUtilsTest
Bug: 119800099
Change-Id: I3570fbc0e4f7079da3315691d676452b17e516a7