fix(plat/mediatek/mt8186): extend MMU region size

fix(plat/mediatek/mt8186): extend MMU region size

In mt8186 suspend/resume flow, ATF has to communicate with a subsys by
read/write the subsys registers. However, the register region of subsys
doesn't include in the MMU mapping region. It triggers MMU faults.

This patch extends the MMU region 0 size to cover all mt8186 HW modules.
This patch also remove MMU region 1 because region 0 covers region 1.

TEST=build pass
BUG=b:202871018

Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
Change-Id: I520c51338578bd68756cd02603ce6783f93daf51