https://bugzilla.redhat.com/show_bug.cgi?id=885380
Use vshCommandOptScaledInt instead of vshCommandOptULongLong so that
values with suffixes can be passed when bytes are being passed along.
Values for the iops parameters still need to be given in the absolute
form as they are not bytes but numbers.
Signed-off-by: Nishith Shah <nishithshah.2211@gmail.com>