Allow mutlichase to use malloc() instead of mmap() for the arena
Allow mutlichase to use malloc() instead of mmap() for the arena

We are working on a project that optmizes tcmalloc in virtualized enviroment.
Multichase helps to track the perofrmance improvements.

Add a new flag -M, which make multichase to use malloc() instead of mmap()
syscall when allocating test arena.

To run with with tcmalloc:

1. build shared multichase:
make LDFLAGS="-g -O3 -pthread" multichase
2. Run with custom malloc library:
LD_PRELOAD=$PATH_TO_TCMALLOC/libtcmalloc.so ./multichase -M

Signed-off-by: Pasha Tatashin <ce4eadb5041f9f427a24f3b8daac1a18b8c25b6e@soleen.com>

google/multichase,google/multichase,google/multichase