For Demura continuous splash hand-off, the DTB must already have
a definition for a demura panel ID. This is necessary
as ABL currently only updates this node and will not add it in
if missing.
Introduce special handling to identify a panel ID of 0 as a dummy
node, and set all invalid cases to the panel id ~0x0.
Change-Id: I70315c1b32cce9bcd2f6142515f2355a489d470b
Signed-off-by: Christopher Braga <cbraga@codeaurora.org>