thermal/intel: Fix intel_tcc_get_temp() to support negative CPU temperature

CPU temperature can be negative in some cases. Thus the negative CPU
temperature should not be considered as a failure.

Fix intel_tcc_get_temp() and its users to support negative CPU
temperature.

Fixes: a3c1f066e1c5 ("thermal/intel: Introduce Intel TCC library")
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Stanislaw Gruszka <stanislaw.gruszka@linux.intel.com>
Cc: 6.3+ <stable@vger.kernel.org> # 6.3+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

thermal/intel: Introduce Intel TCC library

There are several different drivers that accesses the Intel TCC
(thermal control circuitry) MSRs, and each of them has its own
implementation for the same functionalities, e.g. getting the current
temperature, getting the tj_max, and getting/setting the tj_max offset.

Introduce a library to unify the code for Intel CPU TCC MSR access.

At the same time, ensure the temperature is got based on the updated
tjmax value because tjmax can be changed at runtime for cases like
the Intel SST-PP (Intel Speed Select Technology - Performance Profile)
level change.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>