What's New:
- PPU: disallow out-of-bounds BG VRAM tile fetches and return open bus (fixes #298)
- Core: do not skip to the next event if the CPU woke up during a DMA (fixes #297)
- KeyPad: always request IRQs from the emulator (not the calling) thread (fixes #290)
- GameDB: fix entries for a bunch of Classic NES and Famicom Mini titles (fixes #302)
- IO: do not enter STOP mode when it is not implemented
- mGBA log: clear the message buffer after printing the message
- mGBA log: flush STDOUT after each message
- Catch fmt::system_error when fmt::print() fails to write to STDOUT (fixes #301)