x86_64 is used as a baseline: the "x86_64" entry, whatever status it has,
is transformed into "all", and then the other entries in ARCHITECTURES
either dropped or rearranged appropriately.
* atari800_libretro: bumped to version 3.1.0:20210529
* bluemsx_libretro: bumped to version 2.9.0:20210606
* fmsx_libretro: bumped to version 4.9:20210512
* fuse_libretro: bumped to version 1.1.1:20210616
* puae_libretro: bumped to version 2.6.1:20210718
* xrick_libretro: bumped to version 1.0.0.6:20210512
* bsnes_libretro: bumped to version 113.1:20210716
* fbneo_libretro: bumped to version 1.0.0.0:20210718
* fceumm_libretro: bumped to version 0.0.1:20210704
* flycast_libretro: bumped to version 0.1:20210517
* freeintv_libretro: bumped to version 0.0:20210512
* gambatte_libretro: bumped to version 0.5.0:20210708
* genesis_plus_gx_libretro: bumped to version 1.7.4:20210716
* gpsp_libretro: bumped to version 0.91:20210715
* gw_libretro: bumped to version 1.6.2:20210606
* handy_libretro: bumped to version 0.95:20210708
* mame2003_plus_libretro: bumped to version 1.0:20210718
* mednafen_gba_libretro: bumped to version 0.9.36:20210704
* mednafen_ngp_libretro: bumped to version 0.9.36.1:20210607
* mednafen_pce_fast_libretro: bumped to version 0.9.38.7:20210716
* mednafen_pce_libretro: bumped to version 0.9.38.7:20210607
* mednafen_pcfx_libretro: bumped to version 0.9.33.3:20210709
* mednafen_psx_hw_libretro: bumped to version 0.9.44.1:20210603
* mednafen_psx_libretro: bumped to version 0.9.44.1:20210603
* mednafen_saturn_libretro: bumped to version 0.9.45.1:20210609
* mednafen_vb_libretro: bumped to version 0.9.36.1:20210709
* mednafen_wswan_libretro: bumped to version 0.9.35.1:20210607
* mesen_libretro: bumped to version 0.9.4:20210604
* mgba_libretro: bumped to version 0.6.1:20210712
* mupen64plus_next_libretro: bumped to version 1.0:20210615
* nestopia_libretro: bumped to version 1.49:20210619
* neocd_libretro: bumped to version 0.5:20210515
* o2em_libretro: bumped to version 1.18:20210606
* pcsx_rearmed_libretro: bumped to version r22:20210708
* picodrive_libretro: bumped to version 1.92:20210716
* snes9x_libretro: bumped to version 1.60:20210516
* stella_libretro: bumped to version 6.5.3:20210711
* stella2014_libretro: bumped to version 3.9.3:20210711
* vba_next_libretro: bumped to version 1.0.2:20210704
* yabause_libretro: bumped to version 0.9.15:20210703
* reminiscence_libretro: bumped to version 0.3.6:20210512
* atari800_libretro: bumped to version 3.1.0:20201109
* mrboom_libretro: bumped to version 4.9:20201124
* mupen64plus_next_libretro: bumped to version 1.0:20201125
* stella2014_libretro: bumped to version 3.9.3:20201007
* vecx_libretro: bumped to version 1.2:20201018
* scummvm_libretro: bumped to version 2.0.0:20201007
* fbneo_libretro: bumped to version 1.0.0.0:20200925