platform/x86: ideapad-laptop: fix checkpatch warnings, more consistent style

platform/x86: ideapad-laptop: fix checkpatch warnings, more consistent style

Fix all checkpatch warnings. Reorder variable definitions from
longest to shortest. Add more whitespaces for better readability.
Rename variables named `ret` to `err` where appropriate. Reorder
sysfs attributes show/store callbacks and the `ideapad_attributes`
array in lexicographic order. And other minor formatting changes.
No significant functional changes are intended.

Signed-off-by: Barnabás Pőcze <pobrn@protonmail.com>
Link: https://lore.kernel.org/r/20210203215403.290792-25-pobrn@protonmail.com
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>