power: qpnp-fg-gen4: Fix battery temperature delta configuration

Currently, battery temperature delta configuration is allowed for
an incorrect limit. Fix it. Also, add a proper check to allow
temperature hysteresis configuration correctly as it also adds
a dependency to battery temperature delta interrupt. Update the
device tree bindings documentation as well.

CRs-Fixed: 2336539
Change-Id: I916138e8d87b5497abe0a8777a9145471324e260
Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>