memory: pl353: fix mask of ECC page_size config register

memory: pl353: fix mask of ECC page_size config register

[ Upstream commit 25dcca7fedcd4e31cb368ad846bfd738c0c6307c ]

The mask for page size of ECC Configuration Register should be 0x3,
according to  the datasheet of PL353 smc.

Fixes: fee10bd22678 ("memory: pl353: Add driver for arm pl353 static memory controller")
Signed-off-by: gexueyuan <gexueyuan@gmail.com>
Link: https://lore.kernel.org/r/20210331031056.5326-1-gexueyuan@gmail.com
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>