[truetype] Simplify memory management.

Instead of using `Update_Max`, switch to regular FreeType memory
allocation macros, stop pre-allocating the glyph instruction arrays.

* src/truetype/ttgload.c (TT_Load_Simple_Glyph,
TT_Process_Composite_Glyph): Switch to regular memory allocation.
* src/truetype/ttinterp.c (Update_Max): Removed.
(TT_Load_Context): Reallocate stack and free old instructions.
(Modify_CVT_Check, Ins_WS): Switch to regular memory allocation.
* src/truetype/ttinterp.h (Update_Max): Removed.
3 files changed