platform/x86: sel3350-platform: Retain LED state on load and unload

platform/x86: sel3350-platform: Retain LED state on load and unload

When the platform driver is loaded or unloaded, it overwrites the
existing LED states. This can cause a loss of early boot state when the
driver loads, and it can cause the ALARM contact to change state or
flicker.

Explicitly retain the existing LED state to prevent overwriting on
driver load and unload.

Tested-By: Robert Joslyn <robert.joslyn@redrectangle.org>
Reviewed-by: Robert Joslyn <robert.joslyn@redrectangle.org>
Signed-off-by: Brodie Abrew <brodie_abrew@selinc.com>
Link: https://patch.msgid.link/20260507004916.6710-1-brodie_abrew@selinc.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>