mxms_headerlen
size = mxms_headerlen(mxm) + mxms_structlen(mxm);
u8 *desc = mxms + mxms_headerlen(mxm);
u16 size = mxms_headerlen(mxm) + mxms_structlen(mxm);
u16 mxms_headerlen(struct nvkm_mxm *);