ARM: dts: msm: enable AVB 2.0 in linux guest

Enable AVB 2.0 in android guest by upating vbmeta parts and
vendor mount flags.

Change-Id: Id938b1617b90f9532329352050a3f6e105e644c1
Signed-off-by: Venkata Rao Kakani <vkakani@codeaurora.org>