board-8064 msm: Overlap secure and non secure video firmware heaps.

Moves fixed area start address down, so that non secure
video firmware heap and secure video firmware area overlap.
Both use the region in a mutually exclusive manner.
ALso introduce a hole, that can be used by MM heap
lock down for content protection.

Change-Id: Ic240377da25e00423742ccb73dbb60a1ff037e37
Signed-off-by: Deepak Kotur <dkotur@codeaurora.org>
[sboyd: drop board file changes]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>