a5ds: add multicore support ...

Enable cores 1-3 using psci. On receiving the smc call from kernel,
core 0 will bring the secondary cores out pen and signal an event for
the cores. Currently on switching the cores is enabled i.e. it is not
possible to suspend, switch cores off, etc.

Change-Id: I6087e1d2ec650e1d587fd543efc1b08cbb50ae5f
Signed-off-by: Usama Arif <usama.arif@arm.com>

plat/arm: Introduce A5 DesignStart platform. ...

This patch adds support for Cortex-A5 FVP for the
DesignStart program. DesignStart aims at providing
low cost and fast access to Arm IP.

Currently with this patch only the primary CPU is booted
and the rest of them wait for an interrupt.

Signed-off-by: Usama Arif <usama.arif@arm.com>
Change-Id: I3a2281ce6de2402dda4610a89939ed53aa045fab