msm: move fixed area start lower so that 768M systems work

The start of the fixed area was at 0xb0000000, but
on 768M 8960 systems this memory doesn't exist.
Since the start of the fixed area must be the
same on all 8960s, the fixed area start is
lowered to 0xa0000000.

Change-Id: Ia86513b08ebc4d37bd1afca7263d8a409d2a72bb
CRs-Fixed: 349125
Signed-off-by: Larry Bassel <lbassel@codeaurora.org>