mpg123: Update to 1.25.12

libmpg123:

    Fix an out-of-bounds read of maximal two bytes for truncated RVA2 frames (oss-fuzz-bug 15975). The earlier fix around the same location needed one thought more. Actually, another though was needed, oss-fuzz-bug 16009 documents the incomplete fix.
    Fix an invalid write of one zero byte for empty ID3v2 frames that demand de-unsyncing (oss-fuzz-bug 16050).
    Correct preprocessor syntax in mangle.h, no #error in a #define line. (bug 273, thanks to nmlgc).

(nia)