Move SDK system-image source.prop_templates in their own folder. DO NOT MERGE.

This allows to have a different rule to generate the source.properties
based on the templates and place them in a directory that depends on
the current target CPU ABI. In turn this prevents the build from
mixing different source.props when building different targets.

Change-Id: I4a1d9f47426c94f376947ddae8be9f5549331616

Conflicts:
	build/sdk-android-arm64-v8a.atree
	build/sdk-android-x86.atree
	build/sdk-android-x86_64.atree
	sys-img/images_arm64-v8a_source.prop_template
	sys-img/images_x86_64_source.prop_template
10 files changed