fix(mt8196): remove CPU_IDLE_SRAM_BASE entry from plat_mmap

This region is defined in LPM driver. Prefer managing this region in
LPM driver and remove it from plat_mmap and platform_def.h.

Change-Id: I57bfaad88a28d4f29e2b132ba080bc7d5b8248d8
Signed-off-by: Gavin Liu <gavin.liu@mediatek.com>
2 files changed