Merge pull request #10379 from xiexingguo/xxg-wip-bluestore-2016-07-21

os/bluestore: fix bitmap allocating failure if max_alloc_size is 0

Mark's Comments:

This passed Jenkins checks.
This passed "ceph_test_objectstore --gtest_filter=*/2".
This PR did not appear to have a significant impact on performance tests.

Reviewed-by: Mark Nelson <mnelson@redhat.com>

diff --cc src/os/bluestore/BitMapAllocator.cc
Simple merge

diff --cc src/os/bluestore/BlueFS.cc
Simple merge