Improve BUILT_ASSEMBLED_*_MANIFEST checks

They are moved into check-vintf-all, which is more
accurate and do not require building full OS images.

Also move kernel check code down to check_vintf_compatible. There
is no assembled manifest to put kernel configs now, but they are still
required for build time OTA VINTF checks.

Test: builds
Test: change a vintf_fragment file to cause a conflict with main manifest file
(add health@2.0 to boot@1.1.xml), and check_vintf_vendor_log fails

Change-Id: I9791abc440a40e1537b4387eb67575ff2e22df08