shared/validate/validate: Fix bug in ParseUint32Range
shared/validate/validate: Fix bug in ParseUint32Range

The range size of 1000-1001 is 2 not 1.

Signed-off-by: Thomas Parrott <6b778ce645fb0e3dde76d79eccad490955b1ae74@canonical.com>

stgraber/lxd,lxc/lxd,hallyn/lxd,hallyn/lxd,stgraber/lxd,stgraber/lxd,stgraber/lxd,lxc/lxd,lxc/lxd,lxc/lxd,stgraber/lxd,lxc/lxd,stgraber/lxd,hallyn/lxd,hallyn/lxd,stgraber/lxd,hallyn/lxd,lxc/lxd,hallyn/lxd,lxc/lxd