msm: thermal: Add support for requesting optimum current for a rail

Add support for KTM to request for an optimum current value for
any rail, when the temperature reaches a preset threshold.

During boot-up, KTM polls the temperature and makes a request for
optimum current. After boot-up KTM set trip point for preset threshold
and wait for tsens notification and makes a request for optimum
current for pre configured rail. If a specific sensor id is configured,
then it will monitor only that sensor otherwise it will monitor
all tsens.

While probing if it defers at regulator initialization, invoke
initialization again at late initcall rather than defers whole
KTM probe itself so that other boot mitigation will be intact.

CRs-fixed: 596687
Change-Id: I9fa184e4921f440ef5b5539dc9573527140f2207
Signed-off-by: Anji Jonnala <anjir@codeaurora.org>