Fixes for three issues:

Fixes for three issues:

Borland needs malloc.h, and this is a cleaner fix for MSVC too (rather than Define alloca...)

Fix sqrt of small negative numbers in smoothing is psy.c

Uninitialized space in floor0.c lookup struct could cause lpc_clear to
trigger on garbage.

Monty

svn path=/trunk/vorbis/; revision=598