dt-bindings: thermal: k3-j72xx: elaborate on binding description

Elaborate on the function of this device node as well as some of the
properties this node uses.

Signed-off-by: Bryan Brattlof <[e-mail]>
Acked-by: Krzysztof Kozlowski <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Daniel Lezcano <[e-mail]>

Documentation/devicetree/bindings/thermal/ti,j72xx-thermal.yaml

···
 maintainers:
   - Keerthy <[e-mail]>
 
+description: |
+  The TI K3 family of SoCs typically have a Voltage & Thermal
+  Management (VTM) device to control up to 8 temperature diode
+  sensors to measure silicon junction temperatures from different
+  hotspots of the chip as well as provide temperature, interrupt
+  and alerting information.
+
+  The following polynomial equation can then be used to convert
+  value returned by this device into a temperature in Celsius
+
+  Temp(C) = (-9.2627e-12) * x^4 + (6.0373e-08) * x^3 + \
+            (-1.7058e-04) * x^2 + (3.2512e-01) * x   + (-4.9003e+01)
+
 properties:
   compatible:
     enum:
···
     items:
       - description: VTM cfg1 register space
       - description: VTM cfg2 register space
-      - description: VTM efuse register space
+      - description: |
+          A software trimming method must be applied to some Jacinto
+          devices to function properly. This eFuse region provides
+          the information needed for these SoCs to report
+          temperatures accurately.
 
   power-domains:
     maxItems: 1