thermal: tsens: Add support for TSENS min temp and 0C interrupt

Add support to read min_temp sensor, to get least temperature of
all TSENS sensors. Add support to use 0C interrupt, which is
triggered when any sensor temperature falls below SET threshold
and also when all sensor temperatures have passed above RESET threshold,
to clear mitigation.

Change-Id: I59d81dd8730c3021b90d369d036613a9015f76f3
Signed-off-by: Jishnu Prakash <jprakash@codeaurora.org>
Signed-off-by: Siva Kumar Akkireddi <sivaa@codeaurora.org>