thermal:imx_thermal: enter busywait cooling loop when over max CPU temp

thermal:imx_thermal: enter busywait cooling loop when over max CPU temp

Remove the check for temperature being within the min/max range and enter the
busywait cooling loop whenever the CPU temperature is over the critical temp.
This fixes the issue where if a board was booted at a temp greater than
the CPU temperature max, it would skip the loop and never indicate or try
to address the overtemp issue.

Cc: Ye Li <b37916@freescale.com>
Cc: Jason Liu <r64343@freescale.com>
Signed-off-by: Tim Harvey <tharvey@gateworks.com>