vas: Update documentation for chip-id
Update the device-tree documentation to include a note about the
'ibm,chip-id' field in the platform device node for VAS. While here,
remove some trailing spaces.
@@ -14,6 +14,8 @@ Each VAS node contains: ::
compatible: "ibm,power9-vas", "ibm,vas"
+ ibm,chip-id: Chip-id of the chip containing this instance of VAS.
+
ibm,vas-id: unique identifier for each instance of VAS in the system.
reg: contains 8 64-bit fields.
