Log Message:
libretro-fceumm: Update to 20190106

Changes:

* FDS: Fix pointers are not freed when closing rom
* update FDS to use retro_get_memory_data/size for handling modified disks
* FDS: Fix IRQ timing
* state.c: minor update and try to fix big-endian save state issues.
* Updates the apu pulse' sweep unit based on latest sources
* fix irq inhibit flag on frame counter
* fix Dragon Warrior 4 not starting after irq inhibit flag is fixed
* fix typo in dmc irq
* pulse channel, now clocks the length counters when silenced (backport from \ 
mednafen-nes)
* minor pulse channel fixes/clean up
* fixes crash, audio states and comments
* Remove space in core option
* C89 compliance
* Add on/off toggle for NES apu channels - backported from FCEUX. Enabled when \ 
only compiled with DEBUG=1.
* Fix runahead audio issues in high/very high quality
* Fix missing sound state variables for some mappers with expansion audio
* Minor cleanup and libretro.h update
* An additional check is added to RETRO_MEMORY_SAVE_RAM in some cases where a \ 
rom has a battery flag enabled while the mapper assumes it does not. This causes \ 
libretro to initialize an unallocated RAM causing errors at startup. A check to \ 
see if the save ram pointer exist and if the size is not empty. Adding these \ 
checks would also allow libretro to not create a blank .srm file in some cases. \ 
Issue originally is from MMC5.
* 9d9c480, Add core option: RAM power up state
* e07255c , Remove redundant memset() calls
* palette:Labeling and index changes
* Fix autodetection of NES controllers
* Update input settings, allow multi-player without matching CRC
* Use lightgun API for Zapper.