platform/x86: hp-wmi:: Mark driver struct with __refdata to prevent section mismatch...

platform/x86: hp-wmi:: Mark driver struct with __refdata to prevent section mismatch warning

As described in the added code comment, a reference to .exit.text is ok
for drivers registered via module_platform_driver_probe(). Make this
explicit to prevent a section mismatch warning:

	WARNING: modpost: drivers/platform/x86/hp/hp-wmi: section mismatch in reference: hp_wmi_driver+0x8 (section: .data) -> hp_wmi_bios_remove (section: .exit.text)

Fixes: c165b80cfecc ("hp-wmi: fix handling of platform device")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20231004111624.2667753-1-u.kleine-koenig@pengutronix.de
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>