This patch saves the boot parameters provided by the previous bootloader
during cold boot and passes them to Trusty. Commit 06ff251ec introduced
the plat_trusty_set_boot_args() handler, but did not consider the boot
parameters passed by the previous bootloader. This patch fixes that
anomaly.

Change-Id: Ib40dcd02b67c94cea5cefce09edb0be4a998db37
Signed-off-by: Varun Wadekar <vwadekar@nvidia.com>