platform/x86: ideapad-laptop: use sysfs_emit()

platform/x86: ideapad-laptop: use sysfs_emit()

sysfs_emit() has been introduced to make it less ambiguous
which function is preferred when writing to the output
buffer in a device attribute's show() callback. Convert the
ideapad-laptop module to utilize this new helper function.

Signed-off-by: Barnabás Pőcze <pobrn@protonmail.com>
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20210203215403.290792-7-pobrn@protonmail.com
Signed-off-by: Hans de Goede <hdegoede@redhat.com>