spcn: add definitions for the PRS command and modifiers

The structures and values from the SPCN specification document plus
the new PRS modifier 0x1C to retrieve the power supplies watts.

Signed-off-by: Cédric Le Goater <clg@fr.ibm.com>
Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>
1 file changed