EDAC/armada_xp: Use devm_platform_ioremap_resource()

Use the devm_platform_ioremap_resource() helper instead of calling
platform_get_resource() and devm_ioremap_resource() separately. Make the
code simpler without functional changes.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Lv Ruyi <lv.ruyi@zte.com.cn>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Jan Luebbe <jlu@pengutronix.de>
Link: https://lore.kernel.org/r/20220421084621.2615517-1-lv.ruyi@zte.com.cn