feat(mt8189): disable L3C shared SRAM if the bootloader is coreboot

The coreboot of MT8189 does not disable the L3C shared SRAM because the
ramstage still needs access to it. Therefore, we disable it at the
start of ATF.

Change-Id: If87223a1f41afd639859ff0ce80d4e64a9e02a2e
Signed-off-by: Vince Liu <vince-wl.liu@mediatek.corp-partner.google.com>
6 files changed