Texture matrix index

Defines
#define	GX_IDENTITY   60
#define	GX_TEXMTX0   30
#define	GX_TEXMTX1   33
#define	GX_TEXMTX2   36
#define	GX_TEXMTX3   39
#define	GX_TEXMTX4   42
#define	GX_TEXMTX5   45
#define	GX_TEXMTX6   48
#define	GX_TEXMTX7   51
#define	GX_TEXMTX8   54
#define	GX_TEXMTX9   57