GCW0: Add proper reset to the gui;
also reset Burn core when changing sound frequency, because Burn updates
it only on reset and not dynamically unlike sound buffer length.
GCW0: Pre-writing silence into buffer is not needed for SDL
GCW0: Fix reset when changing settings from menu
A68k: Enable a68k in makefiles; fix paths when assembling with nasm

Use the same names for normal and debug builds

Disable debug build by default

A68k: Pass -DFBA_DEBUG to HOSTCFLAGS, this is needed for fba_make68k.c debug build
Don't track gamelist.txt
GCW0: Add wav_exit() stub needed by neo_run.cpp (debug build)
M68k: add m68kdasm to debug build
A68k-x86: Silence nasm 2.10.09 warnings (labels without semicolon)
A68k-mips: Fix a68k-mips core.

  1. Fix m_seh/m_seb macros (should be sra dest,dest,xx)
  2. Add debugging ability (singlestep callback)

A68k-mips: Add macros for ror/rorv by Nebuleon

A68k-mips: Revert Nebuleon macros and use mips32r2 opcodes by default

A68k-mips: Fix debug build

  - Now always save $gp and reload it
  - Add forgotten debug callback before jumping to opcode emulation
M68k: Check function pointers for NULL before calling.

  Check if SekDbgFetch***Disassembler is NULL before calling it in
m68k_read_disassembler_88 macro.
SEK: Fix debug build, initialize function pointers and do cleanup.

SEK: Fix braces in debug build of sek.cpp
GCW0: Implement a simple debugger with gui
GCW0: audio: Check if already initialized before init'ing
A68k-mips: Save real PC to M68000_regs.pc before calling mem callbacks

  A68k-x86, C68k and M68k save real PC before calling mem callbacks, because
SekGetPC maybe used inside (as with Sega games). Previously A68k-mips
was saving pointer (BASEPC+PC) which could cause unpredicted segfaults.
A68k-mips: Fix setting N flag in asl.b 1,reg / bpl combo

  If reg contained 0x80 after shifting left the N flag was receiving
incorrect value 2 (should be 0/1). Now discard higher bits when setting
this flag. This fixes aurail.zip
A68k-mips: Save $gp around calling memory callbacks.

  Reason: in rare occasions $gp is not the same throughout the code,
it is changed in memory callbacks sometimes. After that $gp in a68k.s
becomes invalid and accessing variables via it causes a segfault.
This fixes kov.zip
GCW0: Add missing downscalers for 224x256 and 336x240

  bombjack.zip - 224x256 (previously 256x256) -> 320x240 and 400x240
  gauntlet.zip - 336x240 -> 320x240
SEK: Put force switching to m68k core to a right place, this fixes segfault.

  For some reason force switching to m68k core in case of 68010 or
68EC020 caused a segfault later. If put to the very beginning of
SekInit() it started working correctly.
SEK: Merge normal and breakpoint checking memory functions. Cleanup.
A68k-mips: Save flags to CCR reg before calling debug callback

  Internally flags are held in $s0-$s4, before calling debug callback
render them into usual M68000_regs.CCR register.