feat(imx8mq): add BL31 PIE support

Enable PIE support so the BL31 firmware can be loaded from anywhere
within the OCRAM (SRAM). For the PIE support we only need to replace
the BL31_BASE define by the BL31_START symbol which is a relocatable
and we need to enable it by setting ENABLE_PIE := 1.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Change-Id: Ie6a13e4ae0fdc6627a94798d7a86df7d5b310896
3 files changed