drivers: thermal: virtual-sensor: Add new virtual sensors for SM6150

Add new virtual sensor definitions for cpuss0-max-step and
apc1-max-step for SM6150. This virtual sensor can be used to
monitor the overall temperature of each CPU cluster device.

Change-Id: I4209845ad38a1584c903ac72d4fb01a3d5e33031
Signed-off-by: Manaf Meethalavalappu Pallikunhi <manafm@codeaurora.org>