platform/x86: dell-wmi: Do not match on descriptor GUID modalias

The descriptor GUID is not used to indicate that WMI notifications
in the dell-wmi driver work properly.  As such a modalias should
not be present that causes this driver to load on systems with this
GUID.

Signed-off-by: Mario Limonciello <mario.limonciello@dell.com>
Reviewed-by: Pali Pohar <pali.rohar@gmail.com>
Signed-off-by: Darren Hart (VMware) <dvhart@infradead.org>