create: Check with OROM limit before setting default chunk size

create: Check with OROM limit before setting default chunk size

Make create check with the appropriate meta data handler and see what the
largest chunk size is supported. The current 512K default is not supported
by existing imsm OROM.

[dan.j.williams@intel.com: trim the upper limit to 512k for future oroms]
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>