EmuScreen::deviceLost waited for the boot thread to finish, so that it
wouldn't create the GPU on a lost device. With the main thread joining the
render thread on surfaceDestroyed, backgrounding the app during a slow boot
(like the firmware auto-install from the disc) caused ANRs.
Instead, the boot thread now skips creating the GPU if the device is lost,
and PSP_InitUpdate creates it once rendering resumes, as on libretro.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
