#96 upgrade to libsox_ng

[Martin Guy]

Hi! SoX had a hard fork in May 2024 and https://codeberg.org/sox_ng/sox_ng has fixed
all the CVE security bugs and a lot more. For robustness you may prefer the
bugfix-only series, currently at 14.4.5.1; I assume Imagination doesn't need any of the
new features in the 14.5, 14.6 and 14.7 series.

I got here from a feature request https://sourceforge.net/p/sox/feature-requests/147
but I can't help with providing the win32 libsox.dll it requests as the Windows cross-build
system I use, MXE, only produces .a files.