Separate dexpreopt deps from stripping deps

The strip rule does not need to wait for the boot image to finish,
create a separate DEXPREOPT_STRIP_DEPS list that only contains
tools used by GenerateStripRule in build/soong/dexpreopt/dexpreopt.go.

Bug: 123038675
Test: m checkbuild
Change-Id: I0814c8d99781533f5778e14547d3e9671e06317f