[ALPS08705293] atf_logger: replace ioremap with memremap

[Detail]
The "ioremap" API will verify the alignment condition for the memory
address.
Replace "ioremap" with "memremap" to prevent alignment faults.

[Test]
PDAS pass

MTK-Commit-Id: 9a6def50930b2d24291819d2b66a3eddf9d87d0a

Signed-off-by: Hsin-Hsiung Wang <hsin-hsiung.wang@mediatek.com>
CR-Id: ALPS08705293
Feature: atflog
Change-Id: I8bcb0d5f77595d61e77ad27f4585b81f3e604f4e