statedump: Print curr_stdalloc in mempool statedump ...

 ...for, it is curr_stdalloc that is incremented for every mem_get()
and decremented on every call to mem_put() and can be used to detect
leaks, when cold_count is 0.

Change-Id: I418a132c3ea4c0b99ea5c6840ff3024d8d19ddf4
BUG: 1134221
Signed-off-by: Krutika Dhananjay <kdhananj@redhat.com>
Reviewed-on: http://review.gluster.org/8557
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Humble Devassy Chirammal <humble.devassy@gmail.com>
Reviewed-by: Pranith Kumar Karampuri <pkarampu@redhat.com>
Tested-by: Pranith Kumar Karampuri <pkarampu@redhat.com>