PKG: optimize v2 libretro-scummvm and strip obj. on all

[Apaczer]

• lr-scummvm & lr-scummvm-legacy (strip)
  • strip --strip-unneeded for size
• lr-scummvm (optimize)
  • disable FLUIDSYNTH entirely from build, which improves performance (it is at least somewhat playable at 15fps). Not sure why it does have no penalty on legacy build.
  • add missing Might&Magic subengines (as SCUMMVM wiki says: "Enabling subengine automatically enables engine target, but disabling all engines and enabling only subengine target will not have the subengines enabled"). To be inline with mainstream standalone ScummVM, we would have to enable following "new" engines in the future with this core (but there is no space):
    • kingdom - Kingdom: The Far Reaches
    • hypno - Hypnotix Inc.
    • griffon - The Griffon Legend
    • glk - Glk Interactive Fiction (prv WIP - lot of games with subengines)
    • efh - Escape From Hell
    • dragons - Blazing Dragons
    • dgds - Dynamix Game Development System
    • chewy - Chewy: Esc from F5 (prv WIP)
    • ags - Adventure Game Studio (hundred of games supported)

[Apaczer]

In the end I will be splitting mainstream core into two with HEAVY flag in the future:

• scummvm_heavy_libretro
  • all stable heavy engines (no WIP + ultima1 & madsv2 from WIP as perk)
  • build with HEAVY=1 & LITE=2 flag (enable heavy, and disable all)
• scummvm_libretro
  • rest of stable engines from curret version
  • build with HEAVY=2 & LITE=0 (disable heavy, and enable all)