This patch fixes incorrect setting for DEVICE1_SIZE
for FVP platforms with more than 8 PEs.
The current value of 0x200000 supports only 8 PEs
and causes exception for FVP platforms with the greater
number of PEs, e.g. FVP_Base_Cortex_A65AEx8 with 16 PEs
in one cluster.

Change-Id: Ie6391509fe6eeafb8ba779303636cd762e7d21b2
Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>