Move ART APEX selection logic to core make.

It's moved from art/Android.mk that won't be available in platform
builds without ART sources.

This also ensures we depend on com.android.art directly on
PRODUCT_PACKAGES and not through LOCAL_REQUIRED_MODULES which was the
case in com.android.art-autoselect. When com.android.art is overridden
through an `overrides` field, the logic in main.mk drops it from
PRODUCT_PACKAGES, but it doesn't consider overrides when processing
LOCAL_REQUIRED_MODULES dependencies.

Bug: 172480617
Test: `m` with PRODUCT_ART_TARGET_INCLUDE_DEBUG_BUILD
  set to true and false
Test: `m` on userdebug and eng builds
Change-Id: Ia606de691fe20ac19f2ca9af362408606e71b11c