inflate returns Z_BUF_ERROR both when the output is full and when the
input ends early. sceZlibInflate treated every Z_BUF_ERROR with no
output space left as insufficient output, so a stream cut off after
its last data byte, such as one missing its Adler-32 trailer, reported
0x8112001C when the output capacity equalled its decoded length, and
0x811200FF with any larger buffer. Report insufficient output only
while input remains, as zlib's uncompress2 and miniz's mz_uncompress2
do and as the technical debt entry describes.