Thermal: Intel SoC DTS: Change interrupt request behavior

The interrupt request call in Intel SoC DTS driver may fail if
there is no underlying BIOS support. However, the user space
thermal daemon can still use the thermal zones created by the
SoC DTS driver in polling mode, therefore, instead of bailing
out on interrupt request failures, it is better just to log
a warning message and continue the init process.

Signed-off-by: Brian Bian <brian.bian@intel.com>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>