power: qpnp-charger: fix typo in temp zone logic

When the current temperature zone is warm and returning
back to normal the cool state will be triggered and
temperature should be checked to be less than the
warm battery temperature minus hysteris.

Fix this by changing the larger than to a less than sign.

Change-Id: Ib519fb07b1d1ccd8675347a51d6ea453fbc4e219
Signed-off-by: David Keitel <dkeitel@codeaurora.org>