nvdimm: Fix badblocks clear off-by-one error

nvdimm_clear_badblocks_region() validates badblock clearing requests
against the span of the region, however it compares the inclusive
badblock request range to the exclusive region range. Fix up the
off-by-one error.

Fixes: 23f49844

 ("libnvdimm: rework region badblocks clearing")
Cc: <stable@vger.kernel.org>
Signed-off-by: Chris Ye <chris.ye@intel.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Link: https://lore.kernel.org/r/165404219489.2445897.9792886413715690399.stgit@dwillia2-xfh


Signed-off-by: Dan Williams <dan.j.williams@intel.com>