drivers: thermal: Move various drivers for intel platforms into a subdir

This cleans up the directory a bit, now that we have several other
platforms using platform-specific sub-directories. Compile-tested with
ARCH=x86 defconfig and the drivers explicitly enabled with menuconfig.

Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Zhang Rui <rui.zhang@intel.com>