Clone volume with right size with SolidFire

It is possible to clone a volume with a size greater than
the source volume. When using the SolidFire driver, the volume size
was not passed in the call made to the SolidFire API when
cloning a volume.

It resulted in a cloned volume having the same size as the source
volume but the correct size in the Cinder database.

This changes makes sure the cloned volume has the correct size
by explicitly passing the requested size when calling
the SolidFire API and cloning the volume.

Fixes: bug #1219105
Change-Id: I5628c7fa922780d6b0601e2daa79310a61085edc
Merge "Clone volume with right size with SolidFire"