move apex.go to build/soong

It has a mutator that affects all modules, and thus would be better to
have it within the core build system.

Bug: 112672359
Test: m apex.test; the built apex has additional libs (such as liblog,
libc++, ...) that are dependencies of the ones specified in Android.bp

Change-Id: Ibf99d5a8812ae22893eb575f42da3bba402270c5
5 files changed
tree: 632650751c0f24fad7382127cbdd0507bf8318d9
  1. apexd/
  2. apexer/
  3. testdata/
  4. Android.bp
  5. OWNERS
  6. PREUPLOAD.cfg