Re-add dlmalloc for 32 bit.

It turns out that appportable has a version that calls dlmalloc directly.
Re-add the dlmalloc symbol for 32 bit only as a compatibility shim that
calls malloc.

Bug: 17881362
Change-Id: I8f20963b0b8d323489dc083e4063779e0d1d7447
2 files changed