Default to Speex audio resampler, if it exists.
tuna: set TARGET_ENABLE_NON_PIE_SUPPORT to true.

Tuna hasn't got many closed stuff, but fRom is one of them. Since the fRom binary is compiled with non-PIE support, camera is almost completely borked. Possibly, other stuff is. So, until we manage to recreate an opensource fRom, let linker enable non-PIE binaries.