Input: sun4i-lradc-keys - convert to devm_platform_ioremap_resource()

Use devm_platform_ioremap_resource() to simplify code.

Signed-off-by: Yangtao Li <frank.li@vivo.com>
Link: https://lore.kernel.org/r/20230705052346.39337-7-frank.li@vivo.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>