Stop calling `java -version`, remove HOST_JDK_IS_64BIT_VERSION

All users of this variable have been removed. This command was adding
50-175ms to `lunch` (~15-30%), and was running at least twice (serially)
in every build too.

Test: cs/HOST_JDK_IS_64BIT_VERSION
Test: prebuilts/jdk/jdk8/linux-x86/bin/java -version, is 64-bit.
Change-Id: Ifdd9663b010ec45918b29ac037849f49c8cd8f69