Correct backport of fa3c776f ("Thermal: Ignore invalid trip points")

Backport of 81ad4276 failed to adjust
for intervening ->get_trip_temp() argument type change, thus causing
stack protector to panic.

drivers/thermal/thermal_core.c: In function ‘thermal_zone_device_register’:
drivers/thermal/thermal_core.c:1569:41: warning: passing argument 3 of
‘tz->ops->get_trip_temp’ from incompatible pointer type [-Wincompatible-pointer-types]
   if (tz->ops->get_trip_temp(tz, count, &trip_temp))
                                         ^
drivers/thermal/thermal_core.c:1569:41: note: expected ‘long unsigned int *’
but argument is of type ‘int *’

CC: <stable@vger.kernel.org> #3.18,#4.1
Signed-off-by: Mike Galbraith <umgwanakikbuti@gmail.com>