drivers: thermal: tsens: Introduce reg_fields to deal with register description

drivers: thermal: tsens: Introduce reg_fields to deal with register description

As we add support for newer versions of the TSENS IP, the current
approach isn't scaling because registers and bitfields get moved around,
requiring platform-specific hacks in the code. By moving to regmap, we
can hide the register level differences away from the code.

Define a common set of registers and bit-fields that we care about
across the various tsens IP versions.

Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org>
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>