Move code dealing with rockbox specific buflib allocations into a
rockbox specific file and implement buffer allocation with
malloc/free for warble/stand alone lib.
Based on patch by Sean Bartell.
Change-Id: I8cb85dad5890fbd34c1bb26abbb89c0b0f6b55cf
Reviewed-on: http://gerrit.rockbox.org/144
Tested-by: Nils Wallménius <nils@rockbox.org>
Reviewed-by: Michael Sevakis <jethead71@rockbox.org>
Reviewed-by: Nils Wallménius <nils@rockbox.org>