HID: Ignore battery for Elan touchscreen on HP Envy X360 15-eu0xxx

Battery status is reported for the HP Envy X360 Convertible 15-eu0xxx
even if it does not have a battery. Prevent it from always reporting the
battery as low.

Signed-off-by: Trevor Davenport <trevor.davenport@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>