* src/truetype/ttgxvar.h (MVAR_TAG_XXX): New macros for MVAR tags.
(GX_Value, GX_MVarTable): New structures.
(GX_Blend): Add it.
* src/truetype/ttgxvar.c (GX_VALUE_SIZE, GX_VALUE_CASE,
GX_GASP_CASE): New macros.
(ft_var_get_value_pointer): New auxiliary function to get a pointer
to a value from various SFNT tables already stored in `TT_Face'.
(ft_var_load_mvar): New function.
(TT_Get_MM_Var): Call it.
(tt_done_blend): Updated.