drm/amd/powerplay: added new raven ppsmc messages

#define PPSMC_MSG_SetPhyclkVoltageByFreq        0x26

#define PPSMC_MSG_SetDppclkVoltageByFreq        0x27

#define PPSMC_MSG_SetSoftMinVcn                 0x28

#define PPSMC_Message_Count                     0x29

#define PPSMC_MSG_GetGfxclkFrequency            0x2A

#define PPSMC_MSG_GetFclkFrequency              0x2B

#define PPSMC_MSG_GetMinGfxclkFrequency         0x2C

#define PPSMC_MSG_GetMaxGfxclkFrequency         0x2D

#define PPSMC_MSG_SoftReset                     0x2E

#define PPSMC_Message_Count                     0x2F

typedef uint16_t PPSMC_Result;