Prevent the building of any version of malloc and friends.
Prevent the building of any version of malloc and friends.

This is done because KLEE has its own internal implementation of
malloc, calloc, realloc and free.

ChickenRunjyd/klee-uclibc,klee/klee-uclibc,ChickenRunjyd/klee-uclibc,ChickenRunjyd/klee-uclibc,ChickenRunjyd/klee-uclibc,klee/klee-uclibc,klee/klee-uclibc,klee/klee-uclibc