libretro-fceumm: Update to 20200520

    * user-adjustable Zapper tolerance
    * reduce max Zapper tolerance to 20
    * MMC1 overrides are treated as ines 2.0, so its needs at least default
      values for prgRam and chrRam columns.

      Fixes FF1 pink screen due to unmapped CHRRAM.
    * Use proper geometry when switching NTSC filter on or off –
      – Width changes previously was not respected when using NTSC filter.
      With full use of overscan, NES width
      is 602 px when NTSC filter is used and 256 px on normal
    * Fix build when compiling without NTSC filter support
    * Adjust Zapper tolerance; make Zapper input tolerance circular rather
      than rectangular by default
    * Fix timing when changing from PAL/Dendy to NTSC –
      – Happens when starting with PAL/Dendy region and changing to NTSC can
      cause frame to get stuck in 50 Hz
      – using RETRO_ENVIRONMENT_SET_SYSTEM_AV_INFO should remedy this.
    * NTSC: Remove height doubling/scanline effect –
      – We just use shaders for scanline if needed. NTSC + height doubling
      causes performance hit
      for some slow devices. Any decent platform should be able to handle
      scanline effect shaders at least.
    * ines.c: Simplify rom info logs and cleanup
    * Fk23c: Fix chr issues for some games –
      – Affects mostly waixing using mixed chr rom/ram modes (bit 2 of ram
      config register $A001)
    * Update ines-correct.h –
      – Add overrides for FK23C
      – Move MMC1 overrides
      – Move MMC5 overrides
    * Move overrides out of some mappers –
      Move mapper-based overrides out and use ines-correct.h if possible.
      Affects the following mappers below:
      – Move Cnrom database to ines-correct.h
      – Mapper 201 update
      – Mapper 91: Add Street Fighter III (Submapper 1) to ines-correct.h
      – Add dipswitch notes to m237
      – Update mapper9 (PC10 version of Mike Tyson’s Punch-out)
    * Move battery-backed prg ram override to ines-correct.h
    * Start expanding internal override database (ines-correct.h)

(nia)