Revert "releasetools: Disable host module on darwin"

Revert "conscrypt: Disable host module on darwin"

Revert submission 1385032-mac-required-fix

Reason for revert: breaks the build on aosp-master
Reverted Changes:
I13335299c:releasetools: Disable host module on darwin
I728a4677a:conscrypt: Disable host module on darwin
I8f3435ff1:art: Remove dependencies on platform unavailable m...
Ibb9248ef4:art: Disable host module on darwin
I7db68a629:libcore: Disable host module on darwin

Bug: 163030797
Change-Id: I3b3991b91652c426d8f22d60c59c44d640059619