Update ogg to check the return of all allocs for those on embedded
platforms with guarantees non-ovecommit.  Be aware that these checks
are useless on any modern desktop OS, but that embedded folks with no
MMU and a hard heap boundary will benefit.

Add one new call to bitpacker that will query a write-mode
oggpack_buffer to see if it ran out of memory at some point; there was
no other way to add the error reporting in an ABI-compatible manner
(and it also allows the writepacker to avoid extra checks; it will
just keep going after running out of memory without faulting and state
can be queried later).


svn path=/trunk/ogg/; revision=16016