Enable logging and use __ANDROID__ instead of __BRILLO__.

Drop the __BRILLO__ #define, instead using the existing
__ANDROID__ define set by the toolchain and setting a new
__ANDROID_HOST__ define when building for the host.

Also use Android logging when __ANDROID__ is defined.

Bug: 23358460
Change-Id: I0d86eac8af381b002a3d46d8a95434c7e24518bd
5 files changed