SDL2_ttf: update to 2.20.1.

2.22.1:
* Updated autotools to use ax_compute_relative_paths, fixing homebrew on macOS

2.20.0:
* Added support for building with CMake
* Added TTF_GetFontWrappedAlign() and TTF_SetFontWrappedAlign() to set alignment on wrapped text
* Added functions to render using FreeType LCD algorithm:
    TTF_RenderText_LCD()
    TTF_RenderUTF8_LCD()
    TTF_RenderUNICODE_LCD()
    TTF_RenderText_LCD_Wrapped()
    TTF_RenderUTF8_LCD_Wrapped()
    TTF_RenderUNICODE_LCD_Wrapped()
    TTF_RenderGlyph_LCD()
    TTF_RenderGlyph32_LCD()
* Added TTF_SetFontDirection() and TTF_SetFontScriptName() for additional control over fonts using HarfBuzz
* Updated to FreeType version 2.12.1 and HarfBuzz version 2.9.1, fixing CVE-2018-25032
* Fixed crash when loading fonts at certain sizes on Windows
* Fix memory corruption loading malformed TTF files (CVE-2022-27470)

(wiz)