Fix free_capacity reporting in SolidFire driver
Fix free_capacity reporting in SolidFire driver

The SolidFire driver reports capacity info in bytes, the
capabilities update reports available_GB.  Sadly we neglected
to convert the bytes to gigibytes here which made for a VERY
large backend and caused things like capacity filtering to not
work correctly.

This patch just adds conversion to GiB when reporting capabilities.

Change-Id: I62c6ad2edd8c2ced344df766c198504894f4902b
Closes-Bug: 1284452

mahak/cinder,j-griffith/cinder,leilihh/cinder,CloudServer/cinder,apporc/cinder,bswartz/cinder,JioCloud/cinder,cloudbase/cinder,duhzecca/cinder,Accelerite/cinder,phenoxim/cinder,openstack/cinder,petrutlucian94/cinder,tlakshman26/cinder-bug-fix-volume-conversion-full,nexusriot/cinder,redhat-openstack/cinder,j-griffith/cinder,JioCloud/cinder,Thingee/cinder,petrutlucian94/cinder,julianwang/cinder,Hybrid-Cloud/cinder,saeki-masaki/cinder,Paul-Ezell/cinder-1,alex8866/cinder,openstack/cinder,NeCTAR-RC/cinder,scality/cinder,nexusriot/cinder,NetApp/cinder,apporc/cinder,julianwang/cinder,Datera/cinder,sasukeh/cinder,winndows/cinder,sasukeh/cinder,nikesh-mahalka/cinder,mahak/cinder,leilihh/cinder,takeshineshiro/cinder,github-borat/cinder,winndows/cinder,NetApp/cinder,Paul-Ezell/cinder-1,scality/cinder,tlakshman26/cinder-new-branch,potsmaster/cinder,duhzecca/cinder,tlakshman26/cinder-new-branch,dims/cinder,ge0rgi/cinder,takeshineshiro/cinder,hguemar/cinder,Thingee/cinder,saeki-masaki/cinder,rakeshmi/cinder,dims/cinder,eharney/cinder,blueboxgroup/cinder,tlakshman26/cinder-bug-fix-volume-conversion-full,CloudServer/cinder,Thingee/cinder,abusse/cinder,Akrog/cinder,potsmaster/cinder,Akrog/cinder,alex8866/cinder,tlakshman26/cinder-https-changes,bswartz/cinder,Accelerite/cinder,spring-week-topos/cinder-week,Nexenta/cinder,tlakshman26/cinder-https-changes,manojhirway/ExistingImagesOnNFS,abusse/cinder,Nexenta/cinder,manojhirway/ExistingImagesOnNFS,Datera/cinder,cloudbase/cinder,phenoxim/cinder,hguemar/cinder,rakeshmi/cinder,nikesh-mahalka/cinder,scottdangelo/RemoveVolumeMangerLocks,NeCTAR-RC/cinder,spring-week-topos/cinder-week,redhat-openstack/cinder,github-borat/cinder,eharney/cinder,Hybrid-Cloud/cinder,blueboxgroup/cinder,scottdangelo/RemoveVolumeMangerLocks