platform/x86: dell-wmi-sysman: fix a NULL pointer dereference

An upcoming Dell platform is causing a NULL pointer dereference
in dell-wmi-sysman initialization.  Validate that the input from
BIOS matches correct ACPI types and abort module initialization
if it fails.

Signed-off-by: Mario Limonciello <mario.limonciello@dell.com>
Tested-by: Perry Yuan <perry_yuan@dell.com>
Link: https://lore.kernel.org/r/20210129172654.2326751-1-mario.limonciello@dell.com
[hdegoede@redhat.com: Drop redundant release_attributes_data() call]
Signed-off-by: Hans de Goede <hdegoede@redhat.com>