Detect and use fstat64() when sizeof (off_t) == 4.

Still have a problem of 32 bit systems where sizeof (off_t) == 4
and fstat64() doesn't exist (eg Android). In this case it will just
fail to work correctly at run time. This is bad.
Scripts/android-configure.sh : Drop preset $PREFIX.
configure.ac : Add HOST_TRIPLET.
ALAC : Check return value of of fwrite.

In the process change parameter of alac_encode() function from
int32_t to uint32_t.

Thanks to Richard Ash <richard@audacityteam.org> for the report.
Add support for Album and Track tags in RIFF files

Add support for Album and Track tags in RIFF files in the LIST chunk of WAV
files as per other formats. Patch by Joel Bouchat <bouchat@hotmail.com>
against libsndfile 1.0.24, forward-ported by Richard Ash

Signed-off-by: Erik de Castro Lopo <erikd@mega-nerd.com>