olpc_battery: Ambient temperature is not available on XO-1.5

The XO-1.5 does not support the ambient temperature property.
Create a separate list of properties for that configuration where
ambient temperature is not included, and apply the correct property
list at runtime.

Signed-off-by: Daniel Drake <dsd@laptop.org>
Signed-off-by: Anton Vorontsov <cbouatmailru@gmail.com>